For the deck using ChaosGallantmon, we need to include many LV3 digimon in the deck, especially those come with "when destroyed" (On deletion) effect to make use of ChaosGallantmon's both effects or those LV3 that needs 2 costs to play. BT5 already provided [BT5-072] Fake Agumon Expert and [BT5-071] Guilmon with very useful "On Deletion" effect that is a must to put into the deck. The LV5 digimon [BT2-078] WereGarurumon is the best choice for Dukemon evolution base. This WereGarurumon gives the inheritable effect : When attacking, once per turn, by destroying one of your other digimon, this digimon becomes active. In your turn, you can claim the attack first, then destroy one of your LV3 digimon to make this digimon active again. After that, you can trigger the second effect of Dukemon to play a LV3 from trash without playing its cost. And since this combo would always destroy some digimon in its turn, why not include LV4 [BT2-073] Garurumon, it can help to gain more memory when your other digimon got destroyed