Trumpeting Gnarr

Mutate's central calculus asks you to weigh the value of merging (a bigger body, stacked abilities, one blocker doing the work of two spells) against the tempo cost of not developing a second creature. Stacking here is its own reward. Whenever this specific creature mutates, whether it goes on top of an existing pile or slides underneath one you build later, it kicks out a 3/3 green Beast token, so the stack it lives in keeps generating bodies as you feed cheap augments into it. That partly answers mutate's central liability: dumping your resources into one pile usually means a single removal spell blows up the whole investment, but every merge this creature participates in leaves a replacement behind. Hardcasting it for its printed cost is beside the point; the design lives in the mutate cost, engineered to be found merging rather than deployed as a lone body. It bends a keyword built around verticality (one creature getting taller and meaner) toward horizontal development, giving green-blue mutate a reason to keep merging past the point of diminishing Voltron returns. Each additional merge is another Beast on the table, not just more text piled onto one target.