Hardest hacks you have ever played.

As the topic states, I wanna hear what are the hardest hacks you have ever played.

For me, I'd say probably that one SMB1 hack, I think it was called Super Mario Forever, I'm sure at least some people here know this, I've also heard it being called Super Mario Frustration. Kaizo Mario is also a pretty obvious extreme difficulty hack. There are others, but I won't start listing all of them in this post. Anyway, tell me the hardest hack you've ever played! Also, if you wish, you could provide people a link to the IPS patch of the game (sharing ROM links = punch at the poster).

i had a Debug Hack for OOT....with a Level editor called utility of time. And we put just about every mini boss in Kokiri forest along with the hidden Ar wing. with the morpha in there just for laughs...(the only Boss that would load up right without the game freezing.)

I would have to make a top 5

1: Super mario forever
2: Kaizo Mario
3: Easy Mario (VGZombie)
4: Mega Man Wilys conquest 2
5: Rockman EXILE

*is too lazy to post a patch for SMF*
Kaizo i believe is a ROM, not a patch
Easy Mario is freeware you must get from VGZombie
the last 2 are on the topic i made with mega man hacks

Rockman Exile..

I love the old megaman games but that hack makes it impossible to play without savestates.

Kaizo is not too hard, with savestates that is, i beat both 1 and 2