Felisa, Fang of Silverquill + Nim Deathmantle + Ashnod's Altar + Spiteful Squad
Felisa, Fang of Silverquill
Nim Deathmantle
Ashnod's Altar
Spiteful Squad
Infinite colorless manaInfinite creature tokensInfinite death triggersInfinite creature ETBInfinite creature LTBInfinite creature sacrifice triggersInfinite +1/+1 counters on creatures you control
How it works
Activate Ashnod's Altar by sacrificing Spiteful Squad, adding CC.
Spiteful Squad dies, triggering itself, Felisa and Nim Deathmantle.
Resolve the Spiteful Squad trigger, moving its +1/+1 counters onto another creature you control.
Resolve the Felisa trigger, creating a 2/1 Inkling creature token for each counter that was on Spiteful Squad.
Activate Ashnod's Altar by sacrificing an Inkling, adding CC.
Resolve the Nim Deathmantle trigger from step 2, causing you to pay 4 to return Spiteful Squad from your graveyard to the battlefield, and attach Nim Deathmantle to it.