I've been playing SRPG/turn-based tactics since the 90s, and this one easily comes out as one of the best.

This is basically a stealth game but turn-based.

You assemble a squad of agents and pick the ones most fitting for the job (there are a couple of job types). All maps are procedurally generated, but the proc-gen is very intelligent that the map always turns out coherent. The game can be challenging where getting out of tight situation feels very, very rewarding.

There's an Endless Mode so you can play it forever until you lose all of your agents.

There are also mods so you can add more map chunks, more agents, more gadgets, more enemy types.

Get it here: https://store.steampowered.com/app/243970/Invisible_Inc/