In a shaker with ice, combine simple syrup with peach schnapps, blackberry liqueur, strawberry cordial, and raspberry vodka. Shake.
In a glass with ice, pour what’s in the shaker, then top with seltzer. Garnish, and enjoy.
Notes
If you can’t find simple syrup, you can make it quickly! Simply combine a ratio of 1 cup of water to 1 cup of sugar, boiled down into a syrup. Once your sugar is melted, you have simple syrup. Simple!