Skittering Precursor + Sword of the Meek + Nahiri's Resolve + Phantom Train
Skittering Precursor
Sword of the Meek
Nahiri's Resolve
Phantom Train
Infinite creature LTBInfinite creature ETBInfinite creature sacrifice triggersInfinite death triggersInfinite colorless manaInfinite +1/+1 counters on a creatureInfinite creature tokens with haste
How it works
Activate Phantom Train by sacrificing Sword of the Meek.
Skittering Precursor triggers, creating a 0/1 Eldrazi Spawn creature token.
When the Eldrazi Spawn enters the battlefield as a 1/1 due to Nahiri's Resolve, Sword of the Meek triggers, returning Sword of the Meek from your graveyard to the battlefield attached to the Eldrazi Spawn.