source: Chess24.com
Game: chess
genre: strategy
prize pool: 250'000$
more info: https://chess24.com/en/read/news/mci-day-13-the-chess-king-s-gambit-fails (see linked articles)

There are a ton more of online chess tournaments. For example chess.com title tuesdays:
https://www.chess.com/tournament/live/titled-tuesdays

Chess.com is the most active with several tournaments, then lichess and only partially chess24.