Activate Scuttlemutt's second ability by tapping it, targeting any creature.
Horobi triggers, destroying that creature.
When the creature dies, Scuttlemutt triggers, untapping itself.
Repeat.
 You may also repeat this loop whenever a creature enters the battlefield under an opponent's control.

Destroy each creature that enters the battlefield under an opponent's control

Destroy any number of creatures opponents control

Lock

Horobi, Death's Wail

Thornbite Staff

Scuttlemutt

Activate Scuttlemutt's second ability by tapping it, making any creature you control all colors until end of turn.
Activate Bloom Tender by tapping it, adding {W}{U}{B}{R}{G}.
Activate Seedcradle Witch by paying {2}{W}{G}, giving Bloom Tender +3/+3 until end of turn and untapping it.
Repeat from step 2.

Infinite black mana

Infinite blue mana

Infinitely large creature until end of turn

Infinite red mana

Infinite mana of colors among permanents you control

Seedcradle Witch

Bloom Tender

Activate Scuttlemutt's second ability by tapping it, making any creature you control all colors until end of turn.
Activate Faeburrow Elder by tapping it, adding {W}{U}{B}{R}{G}.
Activate Seedcradle Witch by paying {2}{W}{G}, giving Faeburrow Elder +3/+3 until end of turn and untapping it.
Repeat from step 2.

Faeburrow Elder

Tap Scuttlemutt to make Kiki-Jiki every color.
Tap Kiki-Jiki to make a copy of Norritt.
Tap the copy to untap Kiki-Jiki.
Repeat.

Infinite death triggers

Infinite creature ETB

Infinite creature LTB

Infinite creature sacrifice triggers

Infinite tapped creature tokens with haste

Kiki-Jiki, Mirror Breaker

Norritt

Tap Scuttlemutt to make Kiki-Jiki every color.
Tap Kiki-Jiki to make a copy of Norritt.
Tap the copy to untap Kiki-Jiki.
Repeat.
Cast To Arms! untapping all your creatures.

Infinite creature tokens with haste

To Arms!

Combos with "Scuttlemutt"