Welcome to the Bitcoin forum, this is a nice game concept it's been a while since I've seen a new type of game the last unique gambling site I saw before is still related to Blockchain and you need to guess the last number of the a certain blockchain transaction, where in your platform its placing a bet on which mining pool who's going to find the next block.

The 25% cashback is generous, I tried to connect my wallet to the site but it seems like it's not available yet.