Activate Ashnod's Altar by sacrificing a creature with a +1/+1 counter on it, adding {C}{C}.
The creature dies, triggering Basri's Lieutenant and Odric's Outrider.
Resolve the Basri's Lieutenant trigger, creating a 2/2 Knight creature token.
Resolve the Odric's Outrider trigger, putting a +1/+1 counter on another creature you control.
Repeat.

Infinite creature ETB

Infinite colorless mana

Infinite death triggers

Infinite creature LTB

Infinite creature sacrifice triggers

Basri's Lieutenant

Odric's Outrider

Ashnod's Altar

Activate Phyrexian Altar by sacrificing a creature with a +1/+1 counter on it, adding one mana of any color.
The creature dies, triggering Basri's Lieutenant and Odric's Outrider.
Resolve the Basri's Lieutenant trigger, creating a 2/2 Knight creature token.
Resolve the Odric's Outrider trigger, putting a +1/+1 counter on another creature you control.
Repeat.

Infinite colored mana

Phyrexian Altar

Activate Altar of Dementia by sacrificing a creature with a +1/+1 counter on it.
The creature dies, triggering Basri's Lieutenant and Odric's Outrider.
Resolve the Basri's Lieutenant trigger, creating a 2/2 Knight creature token.
Resolve the Odric's Outrider trigger, putting a +1/+1 counter on another creature you control.
Resolve the Altar of Dementia ability from step 1, causing target player to mill cards equal to the sacrificed creature's power.
Repeat.

Infinite mill

Infinite self-mill

Altar of Dementia

Activate Ashnod's Altar by sacrificing another creature.
When the creature dies, Odric's Outrider triggers, putting a +1/+1 counter on Scurry Oak
Scurry Oak triggers, creating a creature token.
Repeat

Combos with "Odric's Outrider"