Activate Cabal Coffers by paying {2} and tapping it, adding seven {B}.
Activate Mirrex by paying {3} and tapping it, creating a 1/1 artifact creature token.
Activate Hecatomb by tapping an untapped Swamp you control, dealing 1 damage to the artifact creature token.
Dross Scorpion triggers, untapping Candelabra of Tawnos.
Activate Candelabra of Tawnos by paying {3} and tapping it, untapping Cabal Coffers, Mirrex, and a Swamp.
Repeat.
If you started the combo with at least 9 Swamps, you will generate at least one additional mana each loop, which can be used to untap additional Swamps and deal infinite damage to your opponents, or allow you to generate extra creature tokens from Mirrex.

Infinite creature tokens

Infinite damage

Infinite death triggers

Infinite ETB

Infinite LTB

Infinite mana lands you control can produce

Hecatomb

Dross Scorpion

Mirrex

Candelabra of Tawnos

Cabal Coffers

Activate Hecatomb by tapping an untapped Swamp you control, dealing 1 damage to Cacophodon.
Cacophodon triggers twice, untapping two tapped swamps you control.
Activate a Swamp you control by tapping it, adding {B}.
Repeat steps 1-3 until Cacophodon has 4 damage marked on it.
Activate Hecatomb by tapping an untapped Swamp you control, dealing 1 damage to Cacophodon.
Nim Deathmantle triggers and Cacophodon triggers twice.
Resolve the Nim Deathmantle trigger, paying {4} to return Cacophodon to the battlefield.
Resolve both Cacophodon triggers, untapping two tapped Swamps you control.
Repeat from step 1.

Infinite mana permanents you control can produce

Cacophodon

Roaming Throne

Nim Deathmantle

Combos with "Hecatomb"