It cant be countered, cant be the target of spells or abilities (effectively rendering it hexproof), has a ridiculously cheap regeneration cost, a decently intense threat as a 4/4, and costs a measly four mana
Angus Mackenzie $149.99 also
In that case, Dacks Duplicate enters the battlefield as a 0/0 Shapeshifter creature, and will probably die almost immediately, when state-based actions are next performed
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To start powering up your creatures, you have cards like Idolized, which gives your enchanted creature +X/+X for each nonland permanent you control when you attack alone, which only gets better if youre able to stockpile some Junk or Treasure tokens for a bit