Icewind Stalwart in exile (Icewind Stalwart exiled by Glorious Protector).
Glorious Protector and Soulherder on the battlefield.
Steps
At the beginning of your end step, Soulherder's second ability triggers, blinking Glorious Protector.
Glorious Protector leaves and enters the battlefield, returning Icewind Stalwart from exile to the battlefield, and triggering Soulherder's first ability, as well as Icewind Stalwart and Glorious Protector's enters-the-battlefield abilities.
Resolve the Soulherder trigger, putting a +1/+1 counter on it.
Resolve the Glorious Protector trigger, exiling Icewind Stalwart until Glorious Protector enters the battlefield.
Soulherder's first ability triggers, putting a +1/+1 counter on itself.
Resolve the Icewind Stalwart trigger, blinking Glorious Protector.
Repeat from step 2.
Results
Infinite +1/+1 counters on Soulherder.
Infinite blinking of Glorious Protector and non-Angel creatures you control.