
Enchantment
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.

Doubles all counters and tokens, premier +1/+1 counter doubler.

Adds extra counter whenever counters placed, cheap doubler-style effect.

Doubles +1/+1 counters in BG decks, same effect on a body.

Doubles counters placed and adds counters, newer alternative.

Cheap creature that adds extra +1/+1 counter on placement.

Doubles counters on your creatures during combat, similar payoff.

Doubles your counters while halving opponents', counter superfriend.

Doubles counters and tokens symmetrically, green enchantment doubler.
→ Infinite damage, Infinite +1/+1 counters on creatures you control
→ Infinite damage, Infinite +1/+1 counters on a creature
→ Infinite colored mana, Win the game at the beginning of your next upkeep, Infinite +1/+1 counters on creatures you control
→ Infinite colorless mana that can only be spent to activate abilities, Infinite creature tokens, Infinite damage
→ Infinite colored mana, Infinite +1/+1 counters on creatures you control
→ Infinite death triggers, Infinite ETB, Infinite LTB
If a creature you control would enter the battlefield with a number of +1/+1 counters on it, it enters with twice that many instead.
If you control two Branching Evolutions, the number of +1/+1 counters put on a creature is four times the original number. Three Branching Evolutions multiplies the original number by eight, and so on.
If two or more effects attempt to modify how many counters would be put onto a creature you control, you choose the order to apply those effects, no matter who controls the sources of those effects.