Activate Ashnod's Altar by sacrificing Belonging, adding {C}{C}.
When Belonging dies, Nim Deathmantle triggers, causing you to pay {4} to return Belonging from your graveyard to the battlefield and attach Nim Deathmantle to it.
When Belonging enters, it triggers, creating three creature tokens.
Activate Ashnod's Altar by sacrificing a creature token, adding {C}{C}.
Repeat.

Infinite colorless mana

Infinite creature tokens

Infinite creature ETB

Infinite creature LTB

Infinite death triggers

Infinite creature sacrifice triggers

Nim Deathmantle

Ashnod's Altar

Belonging

Activate Eldrazi Displacer by paying {2}{C}, blinking Belonging.
When Belonging enters, it triggers, creating three creature tokens.
Activate Ashnod's Altar by sacrificing two creature tokens, adding {C}{C}{C}{C}.
Repeat.

Infinite blinking

Infinite blinking of most creatures

Eldrazi Displacer

Cast Belonging by paying {5}{W}.
When Belonging enters, it triggers, creating three 1/1 Shapeshifter creature tokens with changeling.
Activate Bloodflow Connoisseur by sacrificing Belonging.
When Belonging dies, Rat King triggers, untapping Rat King.
Resolve the Bloodflow Connoisseur ability.
Activate Rat King by tapping it and sacrificing the Shapeshifters.
When the Shapeshifters die, Rat King triggers three times, untapping Rat King.
Resolve the Rat King ability from step 5, returning Belonging from your graveyard to the battlefield.
Repeat from step 2.

Infinite +1/+1 counters on a creature

Rat King, Verminister

Thornbite Staff

Bloodflow Connoisseur

Cast Belonging by paying {5}{W}.
When Belonging enters, it and Intruder Alarm trigger.
Resolve the Belonging trigger, creating three 1/1 Shapeshifter creature tokens with changeling.
When the Shapeshifters enter, Intruder Alarm triggers three times. Resolve the Intruder Alarm triggers from this step and step 2, untapping all creatures four times.
Activate Woe Strider by sacrificing Belonging.
Activate Rat King by tapping it and sacrificing the Shapeshifters, returning Belonging from your graveyard to the battlefield.
Repeat from step 2.

Combos with "Belonging"