Quickbeam, Upstart Ent + Devoted Druid + Thopter Squadron + Xenograft

Quickbeam, Upstart Ent

Devoted Druid

Thopter Squadron

Xenograft

How it works

1. Activate Devoted Druid's first ability by tapping it, adding .
2. Activate Devoted Druid's second ability by putting a -1/-1 counter on it, untapping it.
3. Activate Devoted Druid's first ability by tapping it, adding .
4. Activate Thopter Squadron's first ability by paying 1 and removing a +1/+1 counter from it, creating a 1/1 Thopter artifact creature token.
5. When the Thopter enters the battlefield as a Treefolk due to Xenograft, Quickbeam triggers, giving Devoted Druid and up to one other creature +2/+2 until end of turn.
6. Activate Thopter Squadron's second ability by paying 1 and sacrificing the Thopter, putting a +1/+1 counter on Thopter Squadron.
7. Activate Devoted Druid's second ability by putting a -1/-1 counter on it, untapping it.
8. Repeat.

This clever loop turns Xenograft into a connective tissue, redefining every creature you control—including Thopter Squadron and its spawned tokens—as a Treefolk so that Quickbeam, Upstart Ent triggers every time a Thopter enters the battlefield. With Xenograft doing the heavy lifting to turn your artifact tokens into honorary Ents, you can use Thopter Squadron's ability to sacrifice a Thopter, which puts a +1/+1 counter back onto Thopter Squadron while fueling the mana needed from Devoted Druid. By repeatedly untapping Devoted Druid using its own -1/-1 counter ability to generate green mana, you fund the loop that continually spits out new Thopters, creating an endless cycle of enters-the-battlefield and sacrifice triggers.