Cast Inside Out by paying {1}{U/R}, targeting Tireless Tribe and then drawing a card.
Activate Tireless Tribe by discarding a card, giving it +4/+0 as its power and toughness are switched.
Repeat step 2 as able.
Deal combat damage to an opponent using Tireless Tribe.

Near-infinite damage to one opponent

Tireless Tribe

Inside Out

Activate Necrotic Ooze using Garth One-Eye's ability by tapping it, causing you to pay {0} to cast a copy of Black Lotus.
Activate Black Lotus by tapping and sacrificing it, adding {G}{G}{G}.
Activate Necrotic Ooze using Barrenton Medic's second ability by putting a -1/-1 counter on it, untapping it.
Activate Necrotic Ooze using Garth One-Eye's ability by tapping it, causing you to pay {1}{G} to cast a copy of Regrowth.
Resolve Regrowth, returning Garth One-Eye to your hand from your graveyard.
Activate Necrotic Ooze using Tireless Tribe's ability by discarding Garth One-Eye, giving Necrotic Ooze +0/+4 until end of turn.
Activate Necrotic Ooze using Barrenton Medic's second ability by putting a -1/-1 counter on it, untapping it.
Repeat.
Once you have infinite {G}, you may sacrifice Black Lotus for any other color of mana, and use that to cast any other spells from Garth One-Eye's ability.

Infinite artifact ETB

Infinite artifact LTB

Infinite artifact sacrifice triggers

Infinite copies of a specific artifact

Infinite card draw for any number of players

Infinite casts of all spells permitted by Garth One-Eye

Infinite colored mana

Infinite creature tokens

Infinite draw triggers for any number of players

Infinite magecraft triggers

Infinite self-discard triggers

Infinite storm count

Infinite creature ETB

Return all cards from your graveyard to your hand

Infinitely powerful creature until end of turn

Garth One-Eye

Necrotic Ooze

Barrenton Medic

Activate Necrotic Ooze using Garth One-Eye's ability by tapping it, causing you to pay {0} to cast a copy of Black Lotus.
Activate Black Lotus by tapping and sacrificing it, adding {G}{G}{G}.
Activate Necrotic Ooze using Devoted Druid's second ability by putting a -1/-1 counter on it, untapping it.
Activate Necrotic Ooze using Garth One-Eye's ability by tapping it, causing you to pay {1}{G} to cast a copy of Regrowth.
Resolve Regrowth, returning Garth One-Eye to your hand from your graveyard.
Activate Necrotic Ooze using Tireless Tribe's ability by discarding Garth One-Eye, giving Necrotic Ooze +0/+4 until end of turn.
Activate Necrotic Ooze using Devoted Druid's second ability by putting a -1/-1 counter on it, untapping it.
Repeat.
Once you have infinite {G}, you may sacrifice Black Lotus for any other color of mana, and use that to cast any other spells from Garth One-Eye's ability.

Devoted Druid

Activate Necrotic Ooze using Garth One-Eye's ability by tapping it, causing you to pay {0} to cast a copy of Black Lotus.
Activate Black Lotus by tapping and sacrificing it, adding {G}{G}{G}.
Activate Necrotic Ooze using Cinderhaze Wretch's second ability by putting a -1/-1 counter on it, untapping it.
Activate Necrotic Ooze using Garth One-Eye's ability by tapping it, causing you to pay {1}{G} to cast a copy of Regrowth.
Resolve Regrowth, returning Garth One-Eye to your hand from your graveyard.
Activate Necrotic Ooze using Tireless Tribe's ability by discarding Garth One-Eye, giving Necrotic Ooze +0/+4 until end of turn.
Activate Necrotic Ooze using Cinderhaze Wretch's second ability by putting a -1/-1 counter on it, untapping it.
Repeat.
Once you have infinite {G}, you may sacrifice Black Lotus for any other color of mana, and use that to cast any other spells from Garth One-Eye's ability.

Cinderhaze Wretch

Combos with "Tireless Tribe"