The lives system really needs to go away now. When you're not extorting the player for quarters, sending the player back several levels after dying a set number of times does not make the game any more challenging. I already completed the last nine levels; making me do them again because I died too many times in level 10 is not a fitting punishment. Actually, you shouldn't be punishing me at all! I'm playing because I want a fun challenge, not because I'm a masochist seeking punishment; if I was, I would play Mario games.
The Kirby games (the platformers, not the spin-offs) were excusable for being less harsh. If you died, you only had to restart the current room; if you ran out of lives, you only had to go back to the start of the level. It's only excusable because it sent you back only a little bit, but it still has the inherent fault with the lives system: making you repeat completed areas as punishment for dying. A lives system works a little better with an open-world game like Kirby And The Amazing Mirror, but save points like in Aquaria would be a lot better.
Using the lives system all but ruins the fun of Gish, a game in which you play as an inexplicably viscous ball of tar, and are punished for trying to have fun with this mechanic. Every time I tried to do something daring, I almost died; every time I tried to grab hard-to-reach coins, I almost died; and since the game tries to be challenging, I ended up being sent back to level one of whatever world I was in a lot. There are also hidden areas whose entrances are in dangerous places, such as on the opposite side of a spike pit, and which you have to hunt for.
Yes, this is only on the “normal” difficulty level, which brings to another fault of the game: the difficulty level only affects how far back you are sent if you run out of lives. Easy: the start of the level (so no different from dying); normal: the start of the world; and hard: the very start of the game. That's insane! Only a glutton for punishment would do that to themselves.
The game should have only a health bar, no lives, and the difficulty level affect the level layout, enemy numbers, damage dealt by hazards, etc. That would be a balanced challenge. It should also let you go back to levels to look for secrets and beat your completion time and score.
I only completed Gish by cheating to give myself infinite lives, and I don't think I would have completed it otherwise. The levels aren't that great to start with — mostly variations of the same few elements: climb walls, slide down narrow passages, flip switches, squash enemies, and grab coins — and when something new is introduced, it's repeated as much as the starting elements.
The boss fights are also pretty lousy. They are all stupidly straightforward, and there isn't much of a challenge, unless you are abysmal at the controls, in which case, you've probably already given up long ago. And I wouldn't blame you. It's fun at first to play a platformer as a gelatinous blob, but the physics puzzles start to get a bit tedious after world two, mainly because of the controls and not because the puzzles are complex. Actually, the puzzles would be really straightforward if controlling the tarball wasn't like trying to manoeuvre a car made of jello.
There's also a hidden boss fight with The Devil. You reach him after completing a hidden area where you run from a ghost through a narrow tunnel filled with indestructible barriers that you have to flip out of the way, which is really difficult since you're just a ball of tar, and there are other enemies on the way, and you only get one go at this. It actually isn't a boss fight: you are given the choice between infinite lives, or a score bonus for squashing Satan. That's a pretty sweet deal either way, but the path there is so insanely hard that the choice might as well not be there, because if you're able to beat this hell tunnel, you're probably not running short on lives.
Gish seems to be trying to be a retro platformer but with a physics engine, and a very squishy player character. In other words, it rides on combining nostalgia with a new gimmick. It even throws in those warp zones that rob you of gameplay, although you at least get to play a cutesy retro-themed level. I only bothered with a couple; the rest are too hard to reach, and I would rather play the main game, because at least it's consistent!
I suppose the important question at this point is whether the blob gimmick is enough to carry a game of this length: only just. Worth a look, but... well, that's it really. Take a look at the demo, then you've seen all that's worth seeing. If you're completely nuts for sadistic platformers, and enjoyed all the Mario games, then you'll probably love this.