One interesting thing about Isshin is that lots of Mardu cards have an attack trigger that says untap your other creatures and theres an additional attack phase. This is an excellent trigger to double, granting you multiple combat steps and potentially killing an opponent or two
Submerge The format desperately needs a response to Being in blue, Submerge likely wouldnt see an oppressive amount of format play, but would be a sure-fire sideboard option against a Bean-heavy meta (Ive used the word Bean an exhausting amount of times, I know)
As a unique Indestructible mana rock with an extra trick up its sleeve, this is the one card to pay attention to
We control both triggers so we can mill and then pay the cost of exiling two cards
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