Dollhouse of Horrors and Goblin Bombardment on the battlefield.
You do not control a Construct.
({1} magic symbol) available.
Steps
Activate Dollhouse of Horrors by paying ({1} magic symbol) , tapping it and exiling Tree of Perdition from your graveyard, creating a token copy of Tree of Perdition that is a 0/0 Construct with haste.
Activate the Tree of Perdition token by tapping it, swapping an opponent's life total with Tree of Perdition's toughness.
Activate Goblin Bombardment by sacrificing the Tree of Perdition token, dealing 1 damage to the opponent whose life total was swapped.
The opponent loses the game due to having zero or les life.