A free app for Windows, by Valve.

Dota Underlords is a strategy game by Valve. The game is based on the contents of DOTA 2, from heroes to killable mobs, skills, and items. Players compete against each other on becoming the last survivor inside a chess board. They hire heroes, collect power-ups, buy upgrades and eliminate every enemy waves. Sometimes they will face another player’s team. Players are rewarded for repelling enemies on the chess board. Each hero has passive synergies and players must match related heroes with similar traits for bonus strength. This game supports cross-play between computer and mobile device users. Everybody can join ranked matchmaking to see who has the best skills and strategy.  There is also an offline mode for practicing against the enemy A.I. or just for casual playing.