Activate Lotus Ring's equip ability by paying {0}, attaching it to Fervent Champion.
Activate Fervent Champion by tapping and sacrificing it, adding {R}{R}{R}.
When Fervent Champion dies, Koll triggers, returning Fervent Champion from your graveyard to your hand.
Cast Fervent Champion by paying {R}.
Repeat.

Infinite colored mana

Infinite death triggers

Infinite ETB

Infinite LTB

Infinite sacrifice triggers

Infinite storm count

Lotus Ring

Koll, the Forgemaster

Fervent Champion

Activate Paradise Mantle by paying {0}, attaching it to Fervent Champion.
Activate Fervent Champion by tapping it, adding {R}.
Activate Skullclamp's ability by paying {0}, attaching it to Fervent Champion.
Fervent Champion dies due to having 0 toughness.
Koll and Skullclamp trigger.
Resolve Skullclamp's trigger, drawing two cards.
Resolve Koll's trigger, returning Fervent Champion from your graveyard to your hand.
Cast Fervent Champion by paying {R}.
Repeat.

Infinite card draw

Infinite draw triggers

Near-infinite death triggers

Near-infinite ETB

Near-infinite LTB

Near-infinite storm count

Paradise Mantle

Skullclamp

Activate Paradise Mantle by paying {0}, attaching it to Fervent Champion.
Activate Fervent Champion by tapping it, adding {R}.
Activate Mortarpod's ability by paying {0}, attaching it to Fervent Champion.
Activate Fervent Champion's ability from Mortarpod by sacrificing it.
Koll triggers, returning Fervent Champion from your graveyard to your hand.
Resolve the Fervent Champion ability, dealing 1 damage to any target.
Cast Fervent Champion by paying {R}.
Repeat.

Infinite damage

Mortarpod

Activate Paradise Mantle by paying {0}, attaching it to Fervent Champion.
Activate Fervent Champion by tapping it, adding {R}.
Activate Mask of Immolation's ability by paying {0}, attaching it to Fervent Champion.
Activate Fervent Champion's ability from Mask of Immolation by sacrificing it.
Koll triggers, returning Fervent Champion from your graveyard to your hand.
Resolve the Fervent Champion ability, dealing 1 damage to any target.
Cast Fervent Champion by paying {R}.
Repeat.

Mask of Immolation

Activate the equipment's equip ability by paying {0}, targeting Fervent Champion.
Crackdown Construct triggers, giving it +1/+1 until end of turn.
Resolve the equipment's ability, attaching it to Fervent Champion.
Repeat.

Infinitely large creature until end of turn

Equipment with Equip Cost = {1}, {2} or {3}

Crackdown Construct

Combos with "Fervent Champion"