Deal damage to Barbed Servitor
Barbed Servitor and Blazing Sunsteel trigger.
Resolve the Barbed Servitor trigger, causing an opponent to lose life equal to the damage dealt to it
Resolve the Blazing Sunsteel trigger, dealing damage to Barbed Servitor.
Repeat from step 2.

Infinite lifeloss

Blazing Sunsteel

Barbed Servitor

Declare any creature as an attacker. Dawnsire triggers, dealing 100 damage to Barbed Servitor.
Barbed Servitor triggers, causing an opponent to lose 100 life.

Near-infinite lifeloss for target opponent

Dawnsire, Sunstar Dreadnought

Deal damage to Barbed Servitor.
Barbed Servitor and Repercussion trigger.
Resolve the Barbed Servitor trigger, causing an opponent to lose life equal to the damage dealt.
Resolve the Repercussion trigger, dealing damage to Barbed Servitor instead of you due to Pariah.
Repeat from step 2.

Repercussion

Pariah

Deal damage to Barbed Servitor
Barbed Servitor and Fiendlash trigger.
Resolve the Barbed Servitor trigger, causing an opponent to lose life equal to the damage dealt to Barbed Servitor.
Resolve the Fiendlash trigger, targeting you, but dealing damage to Barbed Servitor instead due to Pariah's Shield.
Repeat from step 2.

Fiendlash

Pariah's Shield

Cast Volcano Hellion by paying {2}{R}{R}.
When Volcano Hellion enters the battlefield, it triggers, dealing an amount of damage to you and Barbed Servitor equal to an opponent's life total.
Barbed Servitor's third ability triggers, causing the opponent to lose that much life.
The opponent loses the game due to having 0 life.

Target opponent loses the game

Volcano Hellion

Cast Wheel of Misfortune by paying {2}{R}, choosing an arbitrarily large number and having Wheel of Misfortune deal that much damage to Barbed Servitor instead of you due to Pariah if you chose the largest number.
Barbed Servitor triggers, causing an opponent to lose life equal to the damage dealt.

Wheel of Misfortune

Earthbend a basic land you control.
Cast Legolas's Quick Reflexes by paying {G}, targeting the earthbent land.
Activate Earthcraft by tapping the earthbent land, targeting the earthbent land.
The land triggers, causing it to deal damage equal to its power to Barbed Servitor.
Barbed Servitor triggers, causing an opponent to lose that much life.
Resolve the Earthcraft trigger, untapping the earthbent land.
Repeat from step 3.

Combos with "Barbed Servitor"