Underchomp is the true card of strengh it is the second best card in the game and its effect make it crush everything in its way. But it is extremly hard to summon so I recommend fusion subsitute monsters. The strongest card in the game is the creator Daniel which is impossible to destroy. To summon Underchomp you need Three Chain Chomp cards, one red paint, one blue paint, one yellow paint and four fusers. So Underchomp is really hard to summon but the rewards consider a 95 percent chance of winning a duel. So keep an Underchomp handy.