- H
Hadamard splits you into a superposition (|L⟩+|R⟩)/√2: two copies, mirrored across the maze. The mirror copy moves with mirrored controls, and both copies eat. A second H interferes you back, since H·H = I.
- Z
Phase flip takes ghosts from |+⟩ to |−⟩, and |−⟩ ghosts are edible. But Z flips |−⟩ back to |+⟩ too, so don't take two in a row.
- ✕
Interference: when a |+⟩ ghost and a |−⟩ ghost meet, they cancel out.
- 〰
Entanglement: ghosts come in Bell pairs. Eat one and its partner collapses too.
- ?
Schrödinger's Clyde is in two places at once until you observe him (line of sight).
- ◎
EPR portals: opposite corners are entangled.
- ⇥
Tunneling: go through a wall with probability e−0.6·w, where w is the wall thickness.
- 👁
Measurement: when a ghost touches one of your copies, the wavefunction collapses. With 50% chance you were never there.