Weak to mass bounce or repeated songs if you can't stick a midgame board
The downside of this card is that its only a temporary solution, but depending on how big the advantage is, stealing it may win you the game anyway
Similarly, if you sacrifice a creature to activate a mana ability while casting a spell with convoke, that creature won't be on the battlefield when you pay the spell's costs, so you won't be able to tap it for convoke
Then you can flash out a creature to use its ability and trigger that ability at instant speed, such as Eternal Witness, the aforementioned Beast Tracker, or a simple Acidic Slime (which likes Beast Tracker, by the way)
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