Light locks by hitting numbered targets. Lock ball on left ramp. Lock one is lit for you at start of game.
Multiball jackpot shot is the 180 ramp on the far left.
If you just need a few points hitting the ball up top to the saucer is repeatable
You can advance lock progress toward your first multiball by shooting the center lane scoop (right of the ramp)
Be careful if you have at least one ball locked; whoever you're playing with might steal your multiball! (much like with Sorcerer or Taxi)
On some Atlantis you can shoot the jackpot shot from a ball on the center post and right flipper