Ambitious Augmenter [Secrets of Strixhaven]

Increment (Whenever you cast a spell, if the amount of mana you spent is greater than this creature's power or toughness, put a +1/+1 counter on this creature.)

When this creature dies, if it had one or more counters on it, create a 0/0 green and blue Fractal creature token, then put this creature's counters on that token.