(Not PocketTactics staff, just some guy who's played a lot of Slay)
While Antiyoy clearly takes inspiration from Slay, it's different enough that I can't call it a ripoff (in the Ninja Fishing sense). It has enough differences that Threes vs 2048 might be a fair comparison.
- Income in Slay is purely based on tiles-per-region, where in Antiyoy you can build income-boosting buildings connected to your capital.
- While the troop upgrade/strength system seems the same, troops in Antiyoy have limited walk-distance per turn (not a concern in Slay)
- Slay seems to assign each hex to a player and puts cities in any area of 2+ hexes, reminding me a bit of early-game Risk. Antoyoy gives each player one (I've also seen two so far) starting area and leaves the rest of the map blank.
- Outside the Campaign mode, Antiyoy has more granular Skirmish options (including AI-only games).