Deal combat damage to an opponent using Gollum.
Cast Oubliette by paying {1}{B}{B}.
When Oubliette enters the battlefield, it triggers, phasing out Gollum until Oubliette leaves the battlefield.
Cast Volcano Hellion by paying {2}{R}{R}.
When Volcano Hellion enters the battlefield, it triggers, dealing an arbitrarily large amount of damage to you and Volcano Hellion.
Instead of you losing the game as a state-based action, Lich's Mirror causes you to shuffle your hand, graveyard and all permanents you own into your library, causing Gollum to phase in as Oubliette leaves the battlefield, and setting your life total to 20.
At the beginning of your end step, Gollum triggers, causing an opponent to lose life equal to the life you gained this turn.

Infinite lifeloss for target opponent

Volcano Hellion

Lich's Mirror

Gollum, Obsessed Stalker

Oubliette

Cast Volcano Hellion by paying {2}{R}{R}.
When Volcano Hellion enters the battlefield, it triggers, dealing an arbitrarily large amount of damage to you and Volcano Hellion.
Instead of you losing the game as a state-based action, Lich's Mirror causes you to shuffle your hand, graveyard and all permanents you own into your library, causing Defiant Bloodlord to phase in as Oubliette leaves the battlefield, and setting your life total to 20.
Defiant Bloodlord triggers, causing an opponent to lose life equal to the life you gained.

Defiant Bloodlord

Cast Volcano Hellion by paying {2}{R}{R}.
When Volcano Hellion enters the battlefield, it triggers, dealing an arbitrarily large amount of damage to you and Volcano Hellion.
Instead of you losing the game as a state-based action, Lich's Mirror causes you to shuffle your hand, graveyard and all permanents you own into your library, causing Rhox Faithmender to phase in as Oubliette leaves the battlefield, and causing you to gain life equal to twice the amount of damage dealt to you plus 40.

Combos with "Oubliette"