[Question] Unique game mechanics -- The best and the worst

This one is easy for me: Earthworm Jim series hands-down has the most unique gameplay mechanics because unlike Katamari Damacy for example, it doesn't rely on one unique mechanic but instead utilizes numerous unique gameplay mechanics.

One of the most unique and obvious examples is the Lorenzo's Soil level in EWJ2. You have to shoot the ceiling to make the floor rise up throughout the whole level. Auto-scrolling levels, eat your hearts out! And, when you cleared soil it could reveal things like enemy spawn points, or it could cover up enemy spawn points (enemies were ants in that level).

Or, how about the For Pete's Sake level in EWJ1 where you have to keep Pete the dog going, and whip him to make him jump over pits, and defend him from enemies? This was an "escort" mission before the phrase was even coined, but in no other escort scenario do you whip your co-horts with your head.

Or 5 seconds into EWJ1 where you launch a cow. What other game have you launched a cow in lately? I thought so...

There are endless examples in EWJ1 and EWJ2, and I haven't even played the 3d versions because they were so poorly reviewed.

EWJFTW!

P.S. - I'll also mention Tass Times in Tonetown. Sure, it was an average adventure game. But to survive, you had to "blend in" with the inhabitants of the alternate universe you were in. For example, you had to talk like them, dress like them, etc. It was Metal Gear Solid hide & seek action before there was such a thing. Sure beats Snake's cardboard box, eh?

Jam it back in, in the dark.