Declare your commander as an attacker.
Rafiq's first and second abilities trigger.
Resolve the first Rafiq trigger, giving your commander +1/+1 until end of turn.
Resolve the second Rafiq trigger, giving your commander double strike until end of turn.
Deal combat damage to an opponent using your commander, causing at least twenty-two damage to be dealt.
The opponent loses the game due to being dealt twenty-one or more damage by your commander.

Target opponent loses the game

Rafiq of the Many

Belt of Giant Strength

Activate Belt of Giant Strength's equip ability by paying {0}, targeting the creature it is currently attached to.
Crackdown Construct triggers, giving itself +1/+1 until end of turn.
Resolve the Belt of Giant Strength ability, doing nothing.
Repeat.

Infinitely large creature until end of turn

Crackdown Construct

At the beginning of your upkeep, Mayael's Aria triggers, putting a +1/+1 counter on each creature you control, causing you to gain ten life and win the game.

Win the game at the beginning of your next upkeep

Mayael's Aria

Colossus Hammer

Cause another creature to enter the battlefield under your control with at least 20 +1/+1 counters on it due to Master Biomancer.
Simic Ascendancy's second ability triggers, putting 20 growth counters on Simic Ascendancy.
At the beginning of your next upkeep, Simic Ascendancy's third ability triggers, causing you to win the game.

Simic Ascendancy

Master Biomancer

Eldrazi Conscription

Activate Vessel of the All-Consuming by tapping it, dealing at least ten damage to any opponent.
Vessel of the All-Consuming's first and second ability trigger.
Resolve Vessel of the All-Consuming's first trigger, putting a +1/+1 counter on it.
Resolve Vessel of the All-Consuming's second trigger, causing that opponent to lose the game.

Combos with "Belt of Giant Strength"