Another Mastemon deck. Sideboard are cards that could be useful in the deck. Purple Memory Boost are 100% replaceable with Amber Memory Boost when that comes out. Ophanimon Falldown Mode and OG Mastemon are used to cheat out Lucemon or get On Play value from a Gatomon. Geo Greymon and ShineGreymon Ruin are good for tamer synergy. Lucemon Chaos Mode and Creepymon both are good together and apply a lot of pressure. Omnimon Zwart Defeat can be good with all the Recovery the deck can get andalso as a Play with an Effect for ST-10 Mastemon. Ordinemon and DeathXmon are both board clears, with Ordinemon needing a bit more investment with two of your Lv6 digimon as a cost, but can be played at end of turn thanks to all of the free DNA digivolves the deck can get, while DeathXmon requires your opponent to have tamers if you have no board yourself. Ukkomon is just generic filtering. Can't digivolve into any of your gatomon which is fine since you don't mind their on play effects.