At end of combat, if this creature attacked or blocked this combat, remove a +1/+0 counter from it
Its trivial to set up a winning sequence by casting this and following it up the next turn with Craterhoof Behemoth or another Overrun effect
Unfortunately it wont activate its copying ability the turn it transforms, but an extra source of this effect and a little bit of advantage beforehand makes it just as valuable overall
Even if you dont deal a ton of damage this way, triggering saboteur abilities twice is already strong
Besides, a 3/1 lifelink creature can be better than two 1/1 fliers, and thats to say nothing of how unreasonable of a bar Lingering Spirits is
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