What Game Mechanics Do You Like/Dislike?

[ShiraNoMai]

Moony pls, he literally mentioned that at the end of his post

This is a general take on mechanics but I love quality of life improvements on existing/commonplace mechanics. The Pokemon menu design is my easiest example of this. If you consider Generation 1 menu design/layout versus the one in place today, it's a night and day comparison.
 

[Moonface]

I just posted about how the final consequence of being attacked by a facehugger in Alien Resurrection (PS1) results in a death animation I really like, but even as a general mechanic I really like the execution of the whole thing (unless I encounter it first hand, then I kinda hate it but you're supposed to).

So if you get attacked by a facehugger, you get implanted with a chestburster. Removing it requires an item that is incredibly rare, so it's likely you'll only have one in your inventory at any time and very unlikely you'll find another any time soon after you find one, so popping it right away has a high chance of getting yourself impregnated again and just dying when the timer runs out because there's no cure item.

What's nice though is while you're impregnated you obviously can't be attacked by a facehugger again, so the ideal approach is to not pop the removal item until the very last moment. However, the game has a quarantine feature where certain areas of the ship become inaccessible while you're impregnated, so it'll force you to use the item in order to progress. This means if you don't have the item and got impregnated, you can't just run to the level end or try to progress further to where another might be in the level so it encourages you to learn how to optimize using the removal item so you don't just soft lock yourself. 

Out of any game that uses a poison-style mechanic where you have limited time to fix a status ailment that lowers your health and/or makes you die, I feel like this is one of the more unique and interesting ones out there.