Looking for creatures with self-contained exponential growth

I’m looking for creatures that start relatively small and/or slow, but get increasingly powerful if my opponents leave them alone for a few turns.

I’m not really interested in ETB-based creatures. The creature itself should be doing something that builds on itself over multiple turns.

Some examples: \[\[Giant Adephage\]\], \[\[Biowaste Blob\]\], \[\[Spawning Kraken\]\], \[\[Ouroboroid\]\], \[\[Hollowhenge Overlord\]\], \[\[Ornery Tumblewagg\]\]

What other creatures fit this kind of strategy? I’m mainly interested in Simic cards, but I’m open to other colors too.

The idea is to build a deck around copy effects, cloning these creatures to effectively give them an extra turn of growth. Having multiple copies also means my opponents need more than one removal spell to stop me.

[https://scryfall.com/card/voc/36/hollowhenge-overlord](https://scryfall.com/card/voc/36/hollowhenge-overlord)