"Boom, boom, rumboom, boorar, boom boom, dahrar boom boom, dahrar boom..."

Assemble the Entmoot

Creatures you control have reach.
Sacrifice this enchantment: Create three tapped X/X green Treefolk creature tokens, where X is the amount of life you gained this turn. Put a reach counter on each of them.

Tales of Middle-earth Commander

Creatures you control have reach.
Sacrifice Assemble the Entmoot: Create three tapped X/X green Treefolk creature tokens, where X is the amount of life you gained this turn. Put a reach counter on each of them.

"Boom, boom, rumboom, boorar, boom boom, dahrar boom boom, dahrar boom…"

Assemble the Entmoot's activated ability counts the total amount of life you gained without taking into account any life you lost during that turn. For example, if you gained 3 life and lost 3 life earlier in the turn, you'll create three tapped 3/3 green Treefolk creature tokens, then put a reach counter on each of them.