"Scavenger Bingo is gamemode that randomly generates a challenge board for each run. Complete a row of 5 spaces horizontally, vertically, or diagonally on your board to get a bingo. Winning or losing without achieving a bingo will reset your run to Ground Zero."Bingo board progress can be viewed through the scoreboard menu in-game.
If for some godforsaken reason you want to add your own Scavenger Bingo challenges, it should be quite easy (in theory). Create a BingoChallengeDef and fill it out. serverType should inherit from BingoChallengeTrackerServer and is only present on the server. It is set up very similarly to achievements, granting the challenge at an appropriate time. Then call your challenge def's RegisterToCatalog() method. Please keep me aware of issues you may encounter, as external mod support has not been tested.
You can find me on Discord @Groove_Salad#7700