Cast Gatta and Luzzu by paying {2}{W}.
When Gatta and Luzzu enters the battlefield, it triggers, targeting Walking Ballista.
Activate Walking Ballista by removing a +1/+1 counter from it, targeting itself, but instead putting two +1/+1 counters on it due to Gatta and Luzzu and Doc Samson.
Activate Walking Ballista by removing a +1/+1 counter from it, dealing 1 damage to any target.
Repeat from step 3.

Infinite +1/+1 counters on a creature

Infinite damage

Gatta and Luzzu

Doc Samson, Super Psychiatrist

Walking Ballista

Activate Doc Samson by tapping it, adding at least {G}{G}{G}{G}{G}.
Cast Hyrax Tower Scout by paying {2}{G}.
When Hyrax Tower Scout enters the battlefield, it triggers, untapping Doc Samson.
Activate Kogla by paying {1}{G}, returning Hyrax Tower Scout from the battlefield to your hand.
Repeat.

Infinite ETB

Infinite LTB

Infinite colored mana

Infinite mana creatures you control can produce

Infinite storm count

Infinite untap of creatures you control

Kogla, the Titan Ape

Hyrax Tower Scout

Cause Doc Samson to become an artifact using Thran Forge.
Activate Doc Samson by tapping it, adding at least four mana of any color
Activate Voltaic Construct by paying {2}, untapping Doc Samson.
Repeat from step 2.

Infinite untap of artifact creatures you control

Voltaic Construct

Thran Forge

Activate Doc Samson by tapping it, adding at least {G}{G}{G}
Activate Scryb Ranger by returning it from the battlefield to your hand, untapping Doc Samson.
Cast Scryb Ranger by paying {1}{G}.
Repeat.

Infinite landfall triggers

Ashaya, Soul of the Wild

Scryb Ranger

Activate Doc Samson by tapping it, adding at least three mana of any color.
Activate Magus of the Candelabra by paying {2} and tapping it, untapping it and Doc Samson.
Repeat.

Infinite mana lands you control can produce

Infinite mana nontoken creatures you control can produce

Infinite untap of lands you control

Infinite untap of nontoken creatures you control

Magus of the Candelabra

Activate Doc Samson by tapping it, adding at least three mana of any color
Activate Candelabra of Tawnos by paying {2} and tapping it, untapping it and Doc Samson.
Repeat.

Card that Animates an Artifact

Candelabra of Tawnos

Animate Spawning Pit using Karn
Activate Spawning Pit's second ability by removing two charge counters from it due to Blossoming Tortoise, creating a 2/2 Spawn artifact creature token.
Activate Spawning Pit's first ability by sacrificing the Spawn, putting two charge counters on it.
Repeat from step 2.

Infinite death triggers

Infinite sacrifice triggers

Blossoming Tortoise

Spawning Pit

Karn, Silver Golem

Cast Touch of Vitae by paying {2}{G}, targeting Doc Samson.
Activate Quicksilver Elemental by paying {U}, causing it to gain Doc Samson's activated abilities until end of turn.
Activate Quicksilver Elemental using Doc Samson's ability by tapping it, adding at least {U}{U}{U}.
Activate Quicksilver Elemental using Doc Samson's ability granted to it by Touch of Vitae by paying {0}, untapping Quicksilver Elemental.
Repeat from step 2.

Quicksilver Elemental

Touch of Vitae

Activate Power Conduit by tapping it and removing a counter from a permanent you control, putting two +1/+1 counters on Lonis.
Lonis' second ability triggers, creating two Clue artifact tokens.
Activate Clock of Omens by tapping the Clues, untapping Power Conduit.
Repeat.

Infinite tapped Clue tokens

Lonis, Genetics Expert

Clock of Omens

Power Conduit

Combos with "Doc Samson, Super Psychiatrist"