The Ooze + Basking Broodscale + Combine Guildmage

The Ooze

Basking Broodscale

Combine Guildmage

How it works

1. Activate Combine Guildmage's first ability by paying 1 and tapping it.
2. Cast Basking Broodscale by paying 1.
3. When Basking Broodscale enters with a +1/+1 counter on it due to Combine Guildmage, it triggers, creating a 0/1 Eldrazi Spawn creature token that'll also enter with a +1/+1 counter on it.
4. Activate the Eldrazi Spawn by sacrificing it, adding C.
5. When the Eldrazi Spawn dies, The Ooze triggers, creating a Mutagen token.
6. Activate the Mutagen by paying 1, tapping and sacrificing it, putting a +1/+1 counter on Basking Broodscale.
7. Basking Broodscale triggers, creating a 0/1 Eldrazi Spawn creature token that'll enter with a +1/+1 counter on it.
8. Repeat from step 4.