The combination of Steel and Ghost typing offers Doublade unique resistances and immunities, particularly excelling in battles where it can take advantage of its resistances to Normal, Fighting, and Poison-type moves
Note that no particular effect is worth a card, but between an Essence Scatter, a Sinkhole, a Disenchant, and lifegain, this card covers all your bases
Chimil, the Inner Sun Listed at: $27.50 Chimil, the Inner Sun is great to have in any deck whatsoever because it helps to prevent your spells from being countered
They're a creature type that brings constant aggression to the table: they want you to be attacking and playing proactively, and they will reward you for it
You could also use Ivy Lane Denizen here instead of Coat of Arms
The Un- sets have a special tournament rule that says that decks are still legal if some card causes cards to be destroyed or removed