Duelyst

Duelyst is a free-to-play hybrid of digital collectible card game and turn-based tactics by Counterplay Games, a studio led by former Blizzard producer Keith Lee. After an open beta in October 2015 it was fully released on 27 April 2016 for PC, and Bandai Namco later took over publishing.

Two players face each other on a 5 by 9 grid. Each side is led by a general, and you summon minions and cast spells from a custom deck, then move your units across the board until one general falls. The game offered six factions with distinct play styles.

Citing declining player numbers, Counterplay shut down the servers on 27 February 2020. On 10 January 2023 the complete source code and assets were published on GitHub under the CC0 license, as Wikipedia notes.