A consumable card merges two active problem cards into a single new totem, freeing a deck slot.
Adding Jola would have placed Donut's deck one totem over its limit. Rather than discard an existing card or sacrifice Shi Maria, Donut first expends all remaining utility buffs on two problem cards.
She then consumes Combo to merge those two cards into one new creature. The resulting totem is still hostile in temperament but enjoys fighting, and the merge creates enough room to keep Jola active.
Two magical cards spiraling together into a single unfamiliar creature card.
Combo solves Donut's deck-capacity problem while preserving Shi Maria and Jola.