I'm going to let you define "the end" however you want, provided it makes
some sense. End stage, end boss, or at least close enough. Whatever. Basically, you were close, but for one reason or another, just couldn't or didn't want to finish it off.
Here are a few of mine...
Bangai-O (DC) - So if you don't know, Bangai-O is a sort of mech SHMUP. It's different from a lot of SHMUPs though in the sense that there is no auto-scrolling and you can go in any direction. Also it has puzzles. Anyway, the game is relatively tough but not super hard. However, the end stage is like WAY LONGER THAN THE OTHERS, requires a very steady, slow pace (this is a game where you mess up and let too many enemies come at you at once, you're dead within an instant), and then at the end of it you get to a boss who instantly shoots like a million missiles (another part of this game is LOTS OF PROJECTILES) at you and YOU DIE LIKE LESS THAN A SECOND AFTER SEEING HIM. Now, the way the mechanics of the game work is that if you launch your missiles at *just* the right moment, you can deflect some enemy missiles, etc. but after playing the super long stage and getting to the end boss and dying within a second before I even had a chance to try to figure out the timing and then this happening like 5 more times, I just gave up forever. Right at the end.
PS. There is a DS Bangai-O game called Bangai-O Spirits that is pretty awesome if you want to check it out. And it doesn't have a cheap end boss either.
Super Ghouls and Ghosts (SNES) - This game is kind of notoriously tough, and you have to play through the whole thing twice, and blah blah blah. Anyway, played through the whole thing twice, got up to the "fake" end boss the second time, and... that stupid bracelet sucks. I can't figure out how to beat him with the bracelet, which is the only way to get to the true end boss. This is another one too where you have to play through this long stage at a slow, steady pace just to get a few shots at the guy and then do it all over again. I did use the Wii save states to "beat" him (in a really, really cheaty way) just to get a sense of how much life he had and then I went back and used the save states again to try to get consistently good at him before trying it without the save states but... I couldn't even get close to consistency, so I didn't even bother.
Super Hexagon (iPhone) - So if you don't know much about this game, it's relatively short (just 6 stages, and you "beat" each one by surviving a minute) but
really, really hard. After weeks and weeks I got all the way to the last stage and got really good at every pattern it threw at me... except one. It just plain moves too fast for me to get a sense of what I am doing wrong. I even tried looking it up on Youtube and slowing it down and such, but still couldn't figure it out. So yeah, my record is about 30 seconds or so, but without figuring out that one pattern I don't think I will ever get the full minute.
Final Fantasy: Crystal Chronicles (GC) - I honestly forget how close to the end we were, but I remembered looking it up in a FAQ and my cousins and I were almost there. And then life happened and we just sort of went our own ways and stopped getting together for regular video game sessions so we never finished it off.
Patapon (PSP) - This is a fun little rhythm action game that has a really, really terrible design decision. You can get all the way up to almost the end just playing the game straight through, but then it requires some special moves to continue that you have to go find / level-up / I don't even remember what to unlock. Just didn't have the interest to go back a bunch before finishing off the game so I stopped.
Mighty Milky Way (DSi) - I honestly forget why I stopped right near the end of this, there was some nonsense that annoyed me so I gave up.
Punch-Out!! (NES) - Not sure if this quite counts as the end, but I am pretty sure I got to the second to last fighter a few times, just never quite finished the game off.
Your turn.
/EDIT
Ironsword: Wizards & Warriors II - Just remembered this one! Got to the end boss, which turned out to be 4 boss fights in a row (all 4 elementals.) At least I think it was 4 in a row, but I don't think I ever got past the 2nd one? In fact now that I really think about it I think the 2nd boss showed up before you even finished the 1st and so on, it might have been time based? So I just kept getting destroyed when they would start tag teaming me and gave up.
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