Note!! This has been updated! (as of 25 Sept 98)
Critical Depth is the would-be successor to Twisted Metal 2. It's so close, and yet so not.
Critical Depth involves submarine combat, and like TM2, the range of vehicles and special weapons is nicely varied. The colors and backgrounds are very nice indeed. The radar is extremely helpful, especially as it's color-coded just like in TM2, plus the added effect of a sort of "foe identification" when an enemy gets within range.
The point of Critical Depth is to collect 5 alien pods in each level, then race to the Portal (read: exit) before anyone takes the pods away from you. If you're like me, and end up killing everyone else before you get all 5 pods, reaching the Portal isn't much of a problem.
There's not many places to camp (hide and snipe) in CD as there are in TM2. If you do camp, be sure to pick up at least one pod before you hide -- that way, nobody else can complete the level. (If any other sub gets all 5 pods, they will run to the Portal and try to escape! Then you've lost.) The Bermuda Triangle level, in particular, is a real bear -- nowhere safe to hide. I've found that a good tactic is to find the "edge" of the playfield and stay there, up close near the surface so that you have a good view of everyone and everything else. Then just sit there. You can fire your standard torpedos, but don't attempt to fire your special weapon or any kind of weapon pickup like Piranhas, Shakers, etc. Quite often, one or two enemies will start weaving back and forth over a certain "line" in the water. Align yourself along it, just keep firing and sooner or later you'll hit someone. In this position, you are apparently invisible to the game's AI about 90% of the time. As soon as you fire a special or pickup, the AI notices you and someone (or several someones) come to get you.
The sit-and-wait method brings up something else -- this game's levels take forever if you're a camper. By forever, I'm talking 30+ minutes per level. If you're not a camper, I have no idea how long it takes, because camping is the only way to survive. The AI's programming seems designed to have all opponents attack you, instead of everyone else, wherever possible, so it's best to just hide somewhere and keep out of the way until everyone but one other enemy dies.
15 Jun 98: Huzzah! Some codes for Critical Depth. They must all be done quickly during regular gameplay. They are:
Quad Damage
R1, R2, R1, R2, Up, Down, Up, Down
Unlimited Weapons
L1, R1, L1, R1, Up, Down, Left, Down
Speaking of which, I'm not sure how you're supposed to finish this game without the Invincibility code. Having seen what a couple of the bosses are like, particularly Mr. Phatt's jaw-dropping ferocity, it boggles the mind as to how on earth you can finish the game without going through all three (count 'em, three) lives long beforehand.
Do note that Invincibility does not let you keep hold of the pods! You can still lose the pods to Shakers or other weapons, so you can't simply gun'n'run without thought to anyone else.
There are still no passwords to get to the final level, so to see the endings, you'll have to still go through all the levels, but at least with Invincibility, you've got a decent chance at surviving long enough. It's still going to take a long time.
Other fun event: With Invincibility, you can go below critical depth as long as you like! Check out new areas (kinda)! Annoy enemies! Have a whole new way to camp! (Although you really don't need to any more...)
20 Jun 98: Having tested both the Invincibility and Unlimited Weapons, it really speeds up the game. I have no idea how you would pass this game without knowing these codes -- the bosses, particularly Mr. Phatt, are nearly impossible to beat. Having the cheater mode on means you never get any actual points, but so what? I never cared that TM2 didn't keep track of points. I'm in it to see the ending of the game. And it looks like -- without giving anything concrete away -- in most of the endings, people get the shaft. Kind of a drag.
This page has been up for a long time, but the counter was installed 28 Nov 1998.