Instant voice puzzle solution
Hold R1 and press Triangle, Up, Circle, Left, X, Down, Square, Right during game play. Select any sound to solve the game's voice puzzles.

Invincibility
Hold R1 and press Circle, Triangle, Square, X, Down(3), Circle, Triangle, Square, X during game play.

Level select
Hold R1 and press Down, Right, Left, Right, Square, Circle, Square, Triangle, Circle, Square, Right, Left at the first options screen, where Abe says "Hello".

View FMV sequences
Hold R1 and press Up, Left, Right, Square, Circle, Triangle, Square, Right, Left, Up, Right at the first options screen, where Abe says "Hello".

Hints:
Keep an eye on status indicators, and never leave an area without clearing it of Mudokons first.

Chant when you see fireflies.

When confronted by multiple doors inside Scrabania and Paramonia, start with the nearest ones; they're generally easier than the ones you have to climb to reach.

Never pass a rock sack without getting rocks. This is especially true when dealing with Elum.

Tactics:
Observe enemy behavior, and use it against them. Every foe has a flaw: Sligs are trigger-happy. Scrabs hate each other more than they hate you. Paramites are cautious alone, but murderous in packs.

Don't let Mudokons die unless you're going for the bad ending ... and if you're going for the bad ending, kill as many as possible.

Just because something didn't work the first time, doesn't mean it won't work the second time ... but if something doesn't work after four or five tries, then you're using your head to drive nails. Try thinking sideways.

Possess anything and everything that you can, and use them like matches. Knock out chant suppressors with grenades, then possess guys who thought they were safe.

Look behind things for secret areas. Sometimes you need to roll through dark zones, or crouch down behind stuff, to find the secrets.

Never pass up a chance to save a fellow Mudokon. You never know when they'll return the favor.