Labyrinth Adversary is a nice inclusion for our Minotaur Tribal. It has an average body for its mana cost and Trample but its true power lies in its ability that let us pay whenever we attack to make target creature unable to block.
Skophos Reaver gets cut because although it has synergy with our discard strategy, it is more situational and has lesser potential in mid to late game than Labyrinth Adversary.
Sundering Eruption is a MDFC which offers us land removal, but the reason we include it in our Minotaur Tribal is the fact that it can give our creatures evasion by making creatures without flying unable to block so it greatly fits our aggro combat oriented strategy.
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