On Metroid Prime 3 (spoiler-free)
Okay, the game's great. Good interface, blah blah.
MADDENING bit, though. This is along the "walkthroughs should never ever be *required* in order to finish a game" thing, a gripe that many people have in many games. It's generally considered a flaw in a game to have a point of no return, from which your only option is to start at the very beginning, and, to a lesser extent, a point at which the next thing to do is so completely nonintuitive that your only option is to completely explore the massive world.
This goes all the way back, for me, to the Phoenix Cave in FFVI, where, if you saved inside, the only way to progress was to complete the cave and defeat the boss. No way out of the cave aside from beating the boss. So, if you saved over your only save slot and were underleveled enough to make leveling *inside* the cave impossible, your only option was to start the game over from the very beginning. Since that's a good solid 30 or so hours into the game (or like 60, if it's your first time through, as it was mine), that's a bit of an annoyance.
The Zodiac Spear chest thing in FFXII is similar, but less maddening.
In games where you only have one save slot, such as the Metroid Prime series, this is an even more pressing issue.
Go to the GameFAQs forums for Metroid Prime 3 and you'll see a couple hundred threads bitching about, in one way or another, the Energy Cell quest. There is a point in the game, towards the end, where, in order to progress, you need to get a code. In order to get the code, you need six energy cells. The energy cells are found, much like keys in MP2 or artifacts in MP1, *anywhere*. While most of the game is surprisingly linear, with map hints and obvious references helping you along, these energy cells are scattered across the various worlds with absolutely *no* hinting as to their location.
Fortunately, in the progress of the normal plot, you happen upon 5 or 6 of them without any effort. So, for people who never used them, the quest is simple. However, the last 4 or so energy cells are positively *maddening* to get (the Bryyo one took a solid 4-5 hours of wandering around, alone). The thing is, there are slots on the ship for *nine* energy cells.
So, if you go on this ship, and insert your energy cells found normally through the plot into the wrong slots (these yield missile expansions, ship missile expansions, and lore; read: completely fucking useless), then you can be faced with this situation. Two energy cells left. Two slots on the ship for them. Need to find them in order to proceed in the plot.
They can be anywhere. Zero unexplored areas in all of the four worlds and zero map hints (a la Metroid Prime 1) to indicate their general locations. Commence days and days of wandering.
tl;dr: Don't use energy cells on the ship until they're required to advance in the plot; you'll have 150 missiles instead of 145 (oh no! missiles are useless anyway), and you'll be *forced* to consult a walkthrough to continue in the game. And to game designers, put some fucking thought into your design next time, it's a stupid flaw in a game where they're otherwise rare.
EDIT: Okay, after beating the game just now, I'll revise this opinion a bit. Having not checked the Valhalla lore, I didn't know that they give you the general area in which the energy cells are located. This doesn't help for ones like Bryyo's, though. Then again, the satisfaction on finishing Bryyo's quest was quite significant... that quest alone spanned like 10 different sub-puzzles and went from one end of the world to another and back again, while using almost every single suit expansion available as well as a healthy (but not insane) amount of problem solving. Delicious fun.
So it's really no big deal. Christ, though, the amount of missiles given to you in that game was simply *ridiculous*. I ended up with about 150, and never used more than, oh, 30 between weapons refills. Ever. The puzzles just lose some of their fun when there's nothing but another useless missile expansion at the end of them. Well, aside from the spider ball trails, those were fucking sweet as hell.
MADDENING bit, though. This is along the "walkthroughs should never ever be *required* in order to finish a game" thing, a gripe that many people have in many games. It's generally considered a flaw in a game to have a point of no return, from which your only option is to start at the very beginning, and, to a lesser extent, a point at which the next thing to do is so completely nonintuitive that your only option is to completely explore the massive world.
This goes all the way back, for me, to the Phoenix Cave in FFVI, where, if you saved inside, the only way to progress was to complete the cave and defeat the boss. No way out of the cave aside from beating the boss. So, if you saved over your only save slot and were underleveled enough to make leveling *inside* the cave impossible, your only option was to start the game over from the very beginning. Since that's a good solid 30 or so hours into the game (or like 60, if it's your first time through, as it was mine), that's a bit of an annoyance.
The Zodiac Spear chest thing in FFXII is similar, but less maddening.
In games where you only have one save slot, such as the Metroid Prime series, this is an even more pressing issue.
Go to the GameFAQs forums for Metroid Prime 3 and you'll see a couple hundred threads bitching about, in one way or another, the Energy Cell quest. There is a point in the game, towards the end, where, in order to progress, you need to get a code. In order to get the code, you need six energy cells. The energy cells are found, much like keys in MP2 or artifacts in MP1, *anywhere*. While most of the game is surprisingly linear, with map hints and obvious references helping you along, these energy cells are scattered across the various worlds with absolutely *no* hinting as to their location.
Fortunately, in the progress of the normal plot, you happen upon 5 or 6 of them without any effort. So, for people who never used them, the quest is simple. However, the last 4 or so energy cells are positively *maddening* to get (the Bryyo one took a solid 4-5 hours of wandering around, alone). The thing is, there are slots on the ship for *nine* energy cells.
So, if you go on this ship, and insert your energy cells found normally through the plot into the wrong slots (these yield missile expansions, ship missile expansions, and lore; read: completely fucking useless), then you can be faced with this situation. Two energy cells left. Two slots on the ship for them. Need to find them in order to proceed in the plot.
They can be anywhere. Zero unexplored areas in all of the four worlds and zero map hints (a la Metroid Prime 1) to indicate their general locations. Commence days and days of wandering.
tl;dr: Don't use energy cells on the ship until they're required to advance in the plot; you'll have 150 missiles instead of 145 (oh no! missiles are useless anyway), and you'll be *forced* to consult a walkthrough to continue in the game. And to game designers, put some fucking thought into your design next time, it's a stupid flaw in a game where they're otherwise rare.
EDIT: Okay, after beating the game just now, I'll revise this opinion a bit. Having not checked the Valhalla lore, I didn't know that they give you the general area in which the energy cells are located. This doesn't help for ones like Bryyo's, though. Then again, the satisfaction on finishing Bryyo's quest was quite significant... that quest alone spanned like 10 different sub-puzzles and went from one end of the world to another and back again, while using almost every single suit expansion available as well as a healthy (but not insane) amount of problem solving. Delicious fun.
So it's really no big deal. Christ, though, the amount of missiles given to you in that game was simply *ridiculous*. I ended up with about 150, and never used more than, oh, 30 between weapons refills. Ever. The puzzles just lose some of their fun when there's nothing but another useless missile expansion at the end of them. Well, aside from the spider ball trails, those were fucking sweet as hell.