Give Walking Ballista lifelink, if needed.
If Walking Ballista has less than two +1/+1 counters on it, activate Unspeakable Symbol by paying 3 life, putting a +1/+1 counter on Walking Ballista.
Activate Walking Ballista's second ability by removing a +1/+1 counter from it, dealing 4 damage to an opponent or a permanent an opponent controls, and causing you to gain 4 life.
Repeat from step 2.

Infinite damage

Infinite lifegain triggers

Infinite lifegain

Infinite +1/+1 counters on creatures you control

Walking Ballista

Unspeakable Symbol

Tor Wauki the Younger

The Rollercrusher Ride

Activate Deathless Angel twice by paying {W}{W}{W}{W}, giving two creatures an opponent controls indestructible until end of turn.
Deal noncombat damage to one of the indestructible creatures, dealing an increased amount of damage instead due to Tor Wauki the Younger.
Toralf triggers, dealing an amount of damage over the excess damage to the second indestructible creature due to Tor Wauki the Younger.
Toralf triggers, dealing an amount of damage over the excess damage to the first indestructible creature due to Tor Wauki the Younger.
Repeat from step 3 an arbitrarily large number of times.
Resolve a Toralf trigger, dealing infinite damage to any target.

Infinite damage to one opponent

Toralf, God of Fury // Toralf's Hammer

Deathless Angel

Activate Deathbringer Thoctar by removing a +1/+1 counter from it, putting two +1/+1 counters on it due to Vigor.
Activate Deathbringer Thoctar by removing a +1/+1 counter from it, dealing 2 damage to any target.
Repeat as desired.

Vigor

Deathbringer Thoctar

Activate Triskelion by removing a +1/+1 counter from it, putting two +1/+1 counters on it due to Vigor.
Activate Triskelion by removing a +1/+1 counter from it, dealing 2 damage to any target.
Repeat as desired.

Triskelion

Activate Walking Ballista's second ability by removing a +1/+1 counter from it, putting two +1/+1 counters on it due to Vigor.
Activate Walking Ballista's second ability by removing a +1/+1 counter from it, dealing 2 damage to any target.
Repeat as desired.

Activate Anti-Venom using Walking Ballista's ability by removing a +1/+1 counter from it, targeting itself and putting two +1/+1 counters on it due to its replacement effect and Tor Wauki the Younger.
Activate Anti-Venom using Walking Ballista's ability by removing a +1/+1 counter from it, dealing 1 damage to any target.
Repeat.

Combos with "Tor Wauki the Younger"