"Let us start a new reign of terror. I will let you live a fantasy beyond your imagination."

Temporal Extortion

When you cast this spell, any player may pay half their life, rounded up. If a player does, counter Temporal Extortion.
Take an extra turn after this one.

Secret Lair Drop

"The scythe of time or my blade at your throat—the choice is yours."
—Holux, stronghold racketeer

Planar Chaos

When you play Temporal Extortion, any player may pay half his or her life, rounded up. If a player does, counter Temporal Extortion.
Take an extra turn after this one.

As the triggered ability resolves, the active player gets the option to perform the action. If that player declines, the next player in turn order gets the option. As soon as any player performs the action, the spell is countered, but the remaining players still get the option. If all players decline, the spell remains on the stack.

When this spell is cast, its “when you cast” ability triggers and goes on the stack on top of it.