Appa, Steadfast Guardian + Hoarding Broodlord + Restoration Angel

Steps

1. Cast Appa by paying {2}{W}{W}.
2. When Appa enters, its first ability triggers, exiling Restoration Angel with the ability to cast it later from exile.
3. Cast Restoration Angel from exile by paying {0} and tapping Appa and another creature you control.
4. Appa's second ability triggers, creating a 1/1 Ally creature token.
5. When Restoration Angel enters, it triggers, blinking Appa.
6. Repeat from step 2.