The mark is entropy and the blank card is not supposed to be there, so the 30 you see is the correct deck, antimatter can be taken out for something like another dragon, and if you want you can upgrade cards, i made this on a low budget so i didn't, and it is good without upgrading.
Please note this is not meant to beat lvl. 5 or false gods, so if you try be prepared to fail, it can beat t50 but it is mostly made for lvl. 3 and under
The recomended cards for replacing the antimatter are:
nova
bone wall
boneyard (this is risky if they have a shield though)
bone dragon
have fun