Activate any number of lands by tapping them, adding at least {2}{R}{R}.
Cast Relentless Assault by paying {2}{R}{R}, causing you to untap all creatures that attacked this turn and causing you to get an additional combat and main phase after this one.
At the beginning of your combat phase, Helm of the Host triggers, creating a token copy of Eternal Witness with haste.
When the Eternal Witness token enters, it triggers, returning Relentless Assault from your graveyard to your hand.
Deal combat damage to an opponent. Nature's Will triggers, untapping all lands you control.
Move to your next main phase and repeat from step 1.

Infinite ETB

Infinite storm count

Infinite combat phases

Infinite mana lands you control can produce

Infinite creature tokens with haste

Infinite magecraft triggers

Infinite untap of lands you control

Infinite combat damage

Relentless Assault

Helm of the Host

Nature's Will

Eternal Witness

Deal combat damage to an opponent using the creature with Sword of Hearth and Home attached.
Sword of Hearth and Home and Sword of Feast and Famine trigger.
Resolve the Sword of Hearth and Home trigger, blinking Ardent Elementalist and causing you to search your library for a basic land card and put it onto the battlefield.
Ardent Elementalist enters the battlefield, returning Relentless Assault from your graveyard to your hand.
Resolve the Sword of Feast and Famine trigger, causing you to untap all lands you control, and causing the defending player to discard a card.
Move to your postcombat main phase.
Activate any number of lands you control by tapping them, adding at least {2}{R}{R}.
Cast Relentless Assault by paying {2}{R}{R}, causing you to untap all creatures that attacked this turn and to get an additional combat and main phase after this one.
 Repeat.

Infinite LTB

Near-infinite landfall triggers

Put all basic lands from your library onto the battlefield

Sword of Feast and Famine

Sword of Hearth and Home

Ardent Elementalist

Declare Charnelhoard Wurm and Savage Ventmaw as attackers.
Savage Ventmaw triggers, adding {R}{R}{R}{G}{G}{G}.
Deal combat damage to an opponent using Charnelhoard Wurm.
Charnelhoard Wurm triggers, returning Relentless Assault from your graveyard to your hand.
Cast Relentless Assault by paying {2}{R}{R}, causing you to untap all creatures that attacked this turn and to get an additional combat and main phase after this one.
Repeat.

Infinite green mana

Infinite red mana

Charnelhoard Wurm

Savage Ventmaw

Declare Charnelhoard Wurm and Klauth as attackers.
Klauth triggers, adding at least {8}{R}{R} that can only be spent to cast spells.
Deal combat damage to an opponent using Charnelhoard Wurm.
Charnelhoard Wurm triggers, returning Relentless Assault from your graveyard to your hand.
Cast Relentless Assault by paying {2}{R}{R}, causing you to untap all creatures that attacked this turn and to get an additional combat and main phase after this one.
Repeat.

Infinite colored mana that can only be spent to cast spells

Klauth, Unrivaled Ancient

Deal combat damage to an opponent using the creature with Sword of Hearth and Home attached.
Sword of Hearth and Home and Sword of Feast and Famine trigger.
Resolve the Sword of Hearth and Home trigger, blinking Archaeomancer and causing you to search your library for a basic land card and put it onto the battlefield.
Archaeomancer enters the battlefield, returning Relentless Assault from your graveyard to your hand.
Resolve the Sword of Feast and Famine trigger, causing you to untap all lands you control, and causing the defending player to discard a card.
Move to your postcombat main phase.
Activate any number of lands you control by tapping them, adding at least {2}{R}{R}.
Cast Relentless Assault by paying {2}{R}{R}, causing you to untap all creatures that attacked this turn and to get an additional combat and main phase after this one.
 Repeat.

Archaeomancer

Declare Charnelhoard Wurm, Grand Warlord Radha and at least two other creatures as attackers.
Grand Warlord Radha triggers, adding at least {R}{R}{R/G}{R/G}
Deal combat damage to an opponent using Charnelhoard Wurm.
Charnelhoard Wurm triggers, returning Relentless Assault from your graveyard to your hand.
Cast Relentless Assault by paying {2}{R}{R}, causing you to untap all creatures that attacked this turn and to get an additional combat and main phase after this one.
Repeat.
If you attack with at least three additional creatures, this combo nets additional mana.

Grand Warlord Radha

Combos with "Relentless Assault"