As Aclazotz's undead forces approached the temple of Ojer Kaslem, they met a roaring wall of vibrant, flourishing life.

Modern Horizons 3

Branching Evolution

If one or more +1/+1 counters would be put on a creature you control, twice that many +1/+1 counters are put on that creature instead.

The Master discovered a new evolutionary path after tossing a human, a dog, and a cat into a vat of Forced Evolutionary Virus. He called his creations "centaurs" and unleashed them unto the wastes.

Fallout

The Lost Caverns of Ixalan Commander

"Is it the water? The stars? Whatever it is, something incredible is happening here."
—Eris, zoologist, journal entry