Lurking Roper + Elemental Mastery + Prosperous Innkeeper

Lurking Roper

Elemental Mastery

Prosperous Innkeeper

How it works

1. Activate Lurking Roper by tapping it, creating four 1/1 Elemental creature tokens.
2. When the Elementals enter the battlefield, Prosperous Innkeeper's second ability triggers four times.
3. Resolve the first Prosperous Innkeeper trigger, causing you to gain 1 life.
4. Lurking Roper triggers, untapping itself.
5. Repeat.