All permanents on the battlefield (Painter's Servant with "Green" chosen).
You have a way to put a +1/+1 counter on Basking Broodscale.
Steps
Put a +1/+1 counter on Basking Broodscale.
Basking Broodscale triggers, creating a 0/1 Eldrazi Spawn creature token.
When the Eldrazi Spawn enters the battlefield as a green creature due to Painter's Servant, Ivy Lane Denizen triggers, putting a +1/+1 counter on Basking Broodscale.