P.S. I work in finance and sometimes find companies in this industry try way too hard to appeal to the younger generation. Lots of marketing pieces sound like dad jokes.
There are some competitions that are somewhat similar. - Visually, generals.io is pretty similar to Halite-I, but in actuality ends up being a pretty different game. - Halite-I is most similar to the Ants AI Challenge of 2011 (which inspired it). - Halite-II was conceived of as sort of a mix of Halite-I and Planet Wars. - MIT Battlecode is similar in controlling lots of pieces, but the style of game is very different because Halite is all about emergent behaviors in the game whereas traditionally Battlecode hasn't been. They're also very different from the implementation side for the end-user. - Codingame can range from somewhat similar to very, very different.