Summary Prospectus by Investment Company - Form 497K

SUMMARY PROSPECTUS

March 29, 2024

Horizon Tactical Fixed Income Fund

Advisor Class: HTFAX

Institutional Class: HTFIX

Investor Class: HTFNX

Before you invest, you may want to review the Prospectus for the Tactical Income Fund (as defined below), which contains more information about the Tactical Income Fund and its risks. The current statutory Prospectus and Statement of Additional Information ("SAI") dated March 29, 2024, are incorporated by reference into this Summary Prospectus. You can find the Tactical Income Fund's Prospectus, SAI, reports to shareholders, and other information about the Tactical Income Fund online at https://www.horizonmutualfunds.com/tfi-fund.html. You can also get this information at no cost by calling 1-855-754-7932 or by sending an e-mail request to [email protected].

Investment Objective: The investment objective of the Horizon Tactical Fixed Income Fund (the "Tactical Income Fund") is to seek to provide total return through a combination of current income and capital appreciation.

Fees and Expenses of the Tactical Income Fund:

This table describes the fees and expenses that you may pay if you buy, hold and sell shares of the Tactical Income Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)	Advisor Class	Institutional Class	Investor Class
Management Fees	0.60%	0.60%	0.60%
Distribution and/or Service (12b-1) Fees	0.25%	None	0.10%
Other Expenses(1)	0.31%	0.20%	0.20%
Acquired Fund Fees and Expenses (1)(2)	0.33%	0.33%	0.33%
Total Annual Fund Operating Expenses(3)	1.49%	1.13%	1.23%

(1)	"Other Expenses" and "Acquired Fund Fees and Expenses" are estimated for the current fiscal year for the Institutional Class.

(2)	This number represents the combined total fees and operating expenses of the underlying funds owned by the Tactical Income Fund and is not a direct expense incurred by the Tactical Income Fund or deducted from Fund assets.

(3)

Note that the amount of Total Annual Fund Operating Expenses shown in the above table will differ from the ratio to average net assets included in the Tactical Income Fund's financial highlights section of the Prospectus which reflects the operating expenses of the Fund and does not include indirect expenses, but includes the expense reductions generated when the Tactical Income Fund loaned its portfolio securities.

Example: This Example is intended to help you compare the cost of investing in the Tactical Income Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Tactical Income Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Tactical Income Fund's operating expenses remain the same (taking into account the contractual expense limitation). Although your actual costs may be higher or lower, based upon these assumptions your costs would be:

	1 Year	3 Years	5 Years	10 Years
Advisor Class	$152	$471	$813	$1,779
Institutional Class	$115	$359	$622	$1,375
Investor Class	$125	$390	$676	$1,489

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Portfolio Turnover

The Tactical Income Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the Tactical Income Fund's performance. During the fiscal period ended November 30, 2023, the Tactical Income Fund's portfolio turnover rate was 638% of the average value of the portfolio.

Principal Investment Strategies of the Tactical Income Fund

The Tactical Income Fund's investment adviser, Horizon Investments, LLC ("Horizon"), seeks to achieve the Tactical Income Fund's investment objective by allocating to investments across various sectors of the global securities markets. The Tactical Income Fund's investments will be primarily comprised of fixed and floating rate bonds of U.S. and foreign corporate issuers, both those that are investment-grade and non-investment grade (i.e., high yield or "junk" bonds); debt securities issued by the U.S. government and its agencies and instrumentalities (collectively, "U.S. Government Securities"); foreign sovereign debt; preferred stocks; convertible bonds; mortgage-backed securities ("MBS"); and bank loan assignments and participations. Horizon may execute the Tactical Income Fund's strategy by investing in exchange-traded funds ("ETFs") that invest primarily in the foregoing or by investing directly in individual securities or baskets of securities.

Horizon selects and weights securities using a flexible approach that combines active management and quantitative models to allocate the Tactical Income Fund's portfolio. The Tactical Income Fund's strategy is primarily driven by a tactical, systematic approach that uses measures of past return and risk to shift the Tactical Income Fund's holdings towards asset classes determined by Horizon to have high and stable measures of price trends. Depending on market conditions, the Tactical Income Fund may at times focus its investments in particular sectors or areas of the economy. The strategy also incorporates a tactical risk management component that monitors asset class trends on a daily basis, and, if conditions deteriorate, prompts Horizon to reduce the Tactical Income Fund's exposure to that asset class and allocate to more defensive-oriented investments, including, without limitation, U.S. Government Securities and money market instruments. As a result of the Tactical Income Fund's tactical risk management strategy, in certain market conditions up to 100% of the Tactical Income Fund's portfolio may be invested in U.S. Government Securities or money market instruments.

The Tactical Income Fund invests in the securities of non-U.S. issuers, including, without limitation, securities of emerging markets issuers and, while the Tactical Income Fund will invest primarily in U.S. Dollar denominated securities, it may also invest a portion of its assets in non-U.S. Dollar denominated securities. Horizon selects portfolio investments without restriction as to the issuer country, capitalization, currency, maturity or credit quality, and investments are expected to include those rated below investment grade (commonly referred to as "high yield" or "junk" bonds). Potential investments are reviewed for trading efficiency, liquidity, risk/return profile, and fit within overall portfolio diversification needs prior to investment. Horizon generally expects to select individual securities or baskets of securities instead of ETFs when it believes such investments are more cost effective, more operationally efficient or will provide strategic exposure to a specific sector or market segment. Horizon expects to engage in frequent buying and selling of securities to achieve the Tactical Income Fund's objective.

Under normal circumstances, the Tactical Income Fund invests not less than 80% of the value of its net assets in fixed income investments. Horizon defines fixed income investments as including: (i) any debt or debt-related securities, income producing securities, and other instruments or evidences of indebtedness, including bonds, bills, notes (including structured notes), loans, money market instruments, mortgage and asset backed securities, and preferred stocks, and derivative instruments related thereto; and (ii) ETFs and mutual funds that invest primarily in fixed income investments.

Principal Risks of the Tactical Income Fund

Many factors affect the Tactical Income Fund's performance. The Tactical Income Fund's share price changes daily based on changes in market conditions in response to economic, political and financial developments. The direction and extent of those price changes will be affected by the financial condition, industry and economic sector, and geographic location of the securities in which the Tactical Income Fund invests. The Tactical Income Fund is not federally insured or guaranteed by any government agency. You may lose money by investing in the Tactical Income Fund.

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Management Risk. The ability of the Tactical Income Fund to meet its investment objective is directly related to the allocation of the Tactical Income Fund's assets. Horizon may allocate the Tactical Income Fund's investments so as to under-emphasize or over-emphasize investments at the wrong times or under the wrong market conditions, in which case the Tactical Income Fund's value may be adversely affected. Horizon's analysis of industries, companies, economic trends, the relative attractiveness of different securities or other matters could be wrong and may not produce desired results.

Market Risk. Investments in securities in general are subject to market risks that may cause their prices to fluctuate over time. The Tactical Income Fund's investments may decline in value due to factors affecting securities markets generally, or particular countries, segments, economic sectors, industries or companies within those markets. The value of a security may decline due to general economic and market conditions that are not specifically related to a particular issuer. Markets may, in response to governmental actions or intervention, economic or market developments, trade disputes, the spread of infectious illness or other public health issues, geopolitical factors or other external factors, experience periods of high volatility and reduced liquidity, and, in extreme cases, may lead to restrictions and halts. During those periods, the Fund may experience high levels of shareholder redemptions, and may have to sell securities at times when the Fund would otherwise not do so, potentially at unfavorable prices. Certain securities may be difficult to value during such periods.

ETF Risk. To the extent the Tactical Income Fund invests in ETFs, you will indirectly pay fees and expenses charged by the ETFs in addition to the Tactical Income Fund's direct fees and expenses. As a result, the cost of investing in the Tactical Income Fund will be higher than the cost of investing directly in ETF shares and may be higher than other mutual funds that invest directly in stocks and bonds. Each ETF is subject to specific risks, depending on the nature of the ETF and its underlying investments. These risks could include sector risk (increased risk from a focus on one or more sectors of the market), liquidity risk (risk that the Tactical Income Fund cannot dispose of its shares of the ETF promptly without a reduction in value) and risks associated with fixed income securities or foreign currencies.

Fluctuation of Net Asset Value ("NAV"); Unit Premiums and Discounts. The NAV of the shares of the ETFs in which the Tactical Income Fund may invest will generally fluctuate with changes in the market value of the ETF's securities holdings and supply and demand of the ETF's shares on the exchanges on which the ETF's shares are traded. The market prices of an ETF's shares may deviate significantly from the NAV of the ETF's shares during periods of market volatility or reduced liquidity. If the Tactical Income Fund purchases an ETF's shares at a time when the market price is at a premium to the NAV of the ETF's shares or sells at a time when the market price is at a discount to the NAV of the ETF's shares, then the Tactical Income Fund may sustain losses that are in addition to any losses caused by a decrease in NAV.

Fixed Income Risk. The value of investments in fixed income securities and securities in which the underlying investments are fixed income securities are expected to fluctuate with changes in interest rates. Typically, a rise in interest rates causes a decline in the value of the fixed income securities owned by the Tactical Income Fund or its underlying investments. Issuers of floating rate debt are exposed to higher interest payments in a rising rate environment. Issuers may default on interest and principal payments. Generally, securities with lower debt ratings ("junk bonds") have greater credit risk.

Credit Risk. Issuers of fixed-income securities may default on their obligations to make interest and principal payments. Generally, securities with lower debt ratings carry a greater risk that the issuer will default on its payment obligations. Fixed-income securities rated in the fourth classification by Moody's (Baa) and S&P (BBB) or lower (sometimes referred to as "junk bonds") have speculative characteristics and changes in economic conditions or other circumstances are more likely to lead to a weakened capacity of those issuers to make principal or interest payments, as compared to issuers of more highly rated securities. These securities can also be thinly traded or have restrictions on resale, which can make them difficult to sell or adversely affect their market value.

Interest Rate Risk. When the Tactical Income Fund invests in bonds (either directly or through underlying investments), the value of your investment in the Tactical Income Fund will fluctuate with changes in interest rates. Typically, a rise in interest rates causes a decline in the value of bond funds owned by the Tactical Income Fund or its underlying investments. In general, the market price of debt securities with longer maturities will increase or decrease more in response to changes in interest rates than shorter-term securities.

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High Yield or Junk Bond Risk. Lower-quality fixed income securities, known as "high yield" or "junk" bonds, present a significant risk for loss of principal and interest. These bonds offer the potential for higher return, but also involve greater risk than bonds of higher quality, including an increased possibility that the bond's issuer, obligor or guarantor may not be able to make its payments of interest and principal (credit quality risk). These investments are considered to be speculative in nature.

MBS Risk. MBS are subject to credit risk because underlying loan borrowers may default. Additionally, these securities are subject to prepayment risk because the underlying loans held by the issuers may be paid off prior to maturity, reducing overall returns.

Foreign Securities Risk. Investing in securities issued by companies or governments whose location or principal business activities are outside the United States, or investing in American Depositary Receipts ("ADRs") or ETFs focusing on such companies, may involve significant risks not present in domestic investments. There is generally less publicly available information about foreign companies and foreign government debt, and the issuers are generally not uniformly bound by consistent accounting, auditing, and financial reporting requirements and standards of practice comparable to those applicable to domestic issuers. Investments in foreign securities also involve the risk of greater price volatility and possible adverse changes in investment or exchange control regulations or currency exchange rates, expropriation or confiscatory taxation, limitation on the removal of cash or other assets from foreign markets, political or financial instability, or diplomatic and other developments, which could affect such investments.

Non-U.S. Government Debt Risk. An investment in debt obligations of non-U.S. governments and their political subdivisions ("sovereign debt") involves special risks that are not present in corporate debt obligations, including increased volatility and possible foreign government interference. The non-U.S. issuer of the sovereign debt or the non-U.S. governmental authorities that control the repayment of the debt may be unable or unwilling to repay principal or interest when due, and a Fund may have limited recourse in the event of a default. A sovereign debtor's willingness or ability to repay principal and pay interest in a timely manner may be affected by, among other factors, its cash flow situation, the extent of its foreign currency reserves, the availability of sufficient foreign exchange, the relative size of the debt service burden, the sovereign debtor's policy toward its principal international lenders and local political constraints.

Emerging Markets Risk. In addition to the risks generally associated with investing in securities of foreign issuers, countries within emerging markets also may have relatively unstable governments, social and legal systems that do not protect securityholders, economies based on only a few industries, and securities markets that trade a small number of issues.

Foreign Currency Risk. Currency trading risks include market risk, credit risk and country risk. Market risk results from adverse changes in exchange rates in the currencies the Tactical Income Fund's underlying investments are long or short. Credit risk results because a currency-trade counterparty may default. Country risk arises because a government may interfere with transactions in its currency.

Quantitative Model Risk. The Tactical Income Fund's strategy relies heavily on quantitative models and the analysis of specific metrics to construct the Tactical Income Fund's portfolio. The impact of these metrics on a security's performance can be difficult to predict, and securities that previously possessed certain desirable quantitative characteristics may not continue to demonstrate those same characteristics in the future. In addition, relying on quantitative models entails the risk that the models themselves may be limited or incorrect, that the data on which the models rely may be incorrect or incomplete, and that Horizon may not be successful in selecting companies for investment or determining the weighting of particular securities in the Tactical Income Fund's portfolio. Any of these factors could cause the Tactical Income Fund to underperform funds with similar strategies that do not select investments based on quantitative analysis.

Turnover Risk. As a result of its trading strategies, the Tactical Income Fund may sell portfolio securities without regard to the length of time they have been held and will likely have a higher portfolio turnover rate than other mutual funds. Since portfolio turnover may involve paying brokerage commissions and other transaction costs, higher turnover generally results in additional expenses, which may lower the performance of the Tactical Income Fund, and may also

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result in the realization of short-term capital gains. The Tactical Income Fund must generally distribute realized capital gains to shareholders, increasing the Tactical Income Fund's taxable distributions. High rates of portfolio turnover in a given year would likely result in short-term capital gains, which are taxed to shareholders at ordinary income tax rates.

Equity Securities Risk. Preferred stocks are sensitive to interest rate changes, and are also subject to equity risk, which is the risk that stock prices will fall over short or extended periods of time. Equity securities typically have greater price volatility than fixed income securities. The market price of equity securities owned by the Tactical Income Fund may go down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally, particular industries represented by those markets, or factors directly related to a specific company, such as decisions made by its management. The rights of preferred stocks on the distribution of a company's assets in the event of a liquidation are generally subordinate to the rights associated with a company's debt securities.

Convertible Securities Risk. The value of a convertible security is influenced by changes in interest rates (with investment value declining as interest rates increase and increasing as interest rates decline) and the credit standing of the issuer. The price of a convertible security will also normally vary in some proportion to changes in the price of the underlying common stock because of the conversion or exercise feature.

Focus Risk. To the extent that the Tactical Income Fund focuses its investments in particular industries, asset classes or sectors of the economy, any market price movements, regulatory or technological changes, or economic conditions affecting companies in those industries, asset classes or sectors may have a significant impact on the Tactical Income Fund's performance.

Bank Loans Risk. The Fund may invest in ETFs that hold bank loans. Investments in bank loans are subject to the same risks as investments in other types of debt securities, including credit risk, interest rate risk, liquidity risk and valuation risk that may be heightened because of the limited public information available regarding bank loans and because loan borrowers may be leveraged and tend to be more adversely affected by changes in market or economic conditions.

Operational and Technology Risk. Cyber-attacks, disruptions, or failures that affect the Tactical Income Fund's service providers or counterparties, issuers of securities held by the Risk Assist Fund, or other market participants may adversely affect the Tactical Income Fund and its shareholders, including by causing losses for the Tactical Income Fund or impairing its operations.

U.S. Government Securities Risk. The Fund's investment in U.S. government obligations may include securities issued or guaranteed as to principal and interest by the U.S. government, or its agencies or instrumentalities. Payment of principal and interest on U.S. government obligations may be backed by the full faith and credit of the United States or may be backed solely by the issuing or guaranteeing agency or instrumentality itself. There can be no assurance that the U.S. government would provide financial support to its agencies or instrumentalities (including government-sponsored enterprises) where it is not obligated to do so. In addition, U.S. government securities are not guaranteed against price movements due to changing interest rates.

Money Market Fund Risk. An investment in a money market fund is not a bank deposit and is not insured or guaranteed by any bank or any government agency. It is possible for the Tactical Income Fund to lose money by investing in money market funds. The value of money market instruments may be affected by changing interest rates and by changes in the credit ratings of the investments held by the money market fund.

New Fund Risk. The Fund was recently formed and has a limited operating history as of the date of this Prospectus. There can be no assurance that the Fund will grow to or maintain an economically viable size.

Performance

The bar chart illustrates the risks of investing in Investor Class shares of the Tactical Income Fund by showing the Tactical Income Fund's average returns for each calendar year since inception. The Average Annual Total Returns table shows how the Tactical Income Fund's average annual returns compare with those of a broad measure of market performance. The Tactical Income Fund's past performance, before and after taxes, is not necessarily an indication of how the Tactical Income Fund will perform in the future. Updated performance information is available at no cost by visiting www.horizonmutualfunds.com or by calling 1-855-754-7932.

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Calendar Year Return as of December 31
Investor Class

During the period shown in the bar chart, the best performance for a quarter was 4.75% (for the quarter ended December 31, 2023). The worst performance was -1.32% (for the quarter ended March 31, 2023).

Tactical Income Fund
Average Annual Total Returns

For the periods ended December 31, 2023	One Year	Since Inception of Class*
Investor Class
Return Before Taxes	1.94%	1.45%
Return After Taxes on Distributions	0.51%	0.06%
Return After Taxes on Distributions and Sale of Fund Shares	1.13%	0.52%
Advisor Class
Return Before Taxes	N/A	2.00%
Bloomberg US Aggregate Bond Index (reflects no deduction for fees, expenses or taxes)**	5.53%	4.44%

*	Investor Class shares commenced operations on December 20, 2022. Advisor Class shares commenced operations on December 20, 2022. Institutional Class shares had not commenced operations prior to the date of this Prospectus. Index information is since inception of Investor Class shares.

After-tax returns are based on the highest historical individual federal marginal income tax rates, and do not reflect the impact of state and local taxes; actual after-tax returns depend on an individual investor's tax situation and may differ from those shown. If you own shares of the Tactical Income Fund in a tax-deferred account, such as an individual retirement account ("IRA") or a 401(k) plan, after-tax returns are not applicable to your investment. After-tax returns are shown for Investor Class shares only and after-tax returns for other classes will vary to the extent that each class has different expenses. A higher after-tax return results when a capital loss occurs upon redemption and translates into an assumed tax deduction that benefits the shareholder.

The Bloomberg US Aggregate Bond Index is a market-capitalization-weighted index that covers the USD denominated, investment-grade (rated Baa3 or above by Moody's), fixed-rate, and taxable areas of the bond market. Index returns do not reflect the effects of fees or expenses. Investors cannot invest directly in an index or benchmark.

Returns would have been lower if Horizon had not waived and/or reimbursed certain expenses of the Defensive Core Fund during the periods shown.

Investment Adviser

The investment adviser to the Tactical Income Fund is Horizon Investments, LLC.

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Portfolio Managers

Scott Ladner, Chief Investment Officer of Horizon, Mike Dickson, Ph.D., Head of Research and Quantitative Strategies of Horizon, and Zachary F. Hill, CFA, Head of Portfolio Management of Horizon, share responsibility for the day-to-day management of the Tactical Income Fund as Co-Portfolio Managers. Mr. Ladner, Dr. Dickson, and Mr. Hill have been Co-Portfolio Managers of the Tactical Income Fund since its inception in 2022.

Purchase and Sale of Fund Shares

You may purchase and redeem shares of the Tactical Income Fund on any day that the New York Stock Exchange is open for trading, subject to certain restrictions described under the section titled "How to Purchase Shares" and "How to Redeem Shares" of the Tactical Income Fund's Prospectus. Purchases and redemptions may be made by mailing an application or redemption request to Horizon Funds c/o U.S. Bank Global Fund Services, P.O. Box 701, Milwaukee, WI 53201-0701, or by calling 1-855-754-7932. You also may purchase and redeem shares through a financial intermediary. The minimum initial investment in the Tactical Income Fund is $2,500 and the minimum subsequent investment is $250 for Advisor Class and Investor Class shares. The minimum initial investment in the Tactical Income Fund is $10 million for Institutional Class shares. There is no minimum subsequent investment for Institutional Class shares.

Tax Information

The Tactical Income Fund's distributions are taxed as ordinary income or capital gains, unless you are investing through a tax- deferred arrangement, such as a 401(k) plan or an individual retirement account. Such tax-deferred arrangements may be taxed later upon withdrawal of monies from those arrangements.

Payments to Broker-Dealers and Other Financial Intermediaries

If you purchase the Tactical Income Fund through a broker-dealer or other financial intermediary (such as a bank), the Tactical Income Fund and its related companies may pay the intermediary for the sale of Fund shares and related services. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary and your salesperson to recommend the Tactical Income Fund over another investment. Ask your salesperson or visit your financial intermediary's website for more information.

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