This video covers most of the collectibles in Snowy Mountain, including but not limited to the somewhat hidden Yellow Eco vent switch, two battering ram lurkers, and a plethora of barrier buttons.
In case it wasn't obvious, yes, those snowy lurkers with the wolf pelts really do respawn infinitely.
0:56 - Those icicle enemies are pretty unique considering how few of them there are in the game. In fact, those might be the least common enemy that's not a boss. Even if they are not, there certainly aren't that many similar enemies in this game.
Dealing with the ice in this game is harder than it may seem. The controls for icy stuff in the Crash Bandicoot games was much better and smoother, in my opinion.
5:02 - Just proving that you MUST be charged with Red Eco in order to fight these shield-wielding lurkers operating the battering rams. No matter how many times you smack them, it just doesn't matter while they have a shield. Fortunately, Red Eco vents are close to each of the three in this level.
5:24 - Despite being considered "hidden", the path to the Yellow Eco vent switch really isn't that well hid. Besides the entrance being rather conspicuous and unusual in and of itself, Willard (as shown earlier) will tell you about the location if you've bought all four Power Cells from him and Gordy and if you've cleared the gnawing lurkers in Spider Cave. The Yellow Eco Power Cells in Mountains Pass and Volcanic Crater are far better examples of truly "hidden" Cells.
I'm not normally the kind of person to point out this sort of thing, but the precursor pistons in the path to the vent switch always looked very... "suggestive" to me. I still wonder whether that was a bizarre coincidence or if somebody purposefully snuck that in a more kid-friendly game.
9:45 - I have no idea whether you're supposed to be able to do that, but you can and it's surely great for saving some time by more quickly heading to an important area.
I wrap up the remainder of Snowy Mountain, Volcanic Crater, Spider Cave, AND Mountain Pass in this video.
Okay, so I did get through this level in just two videos when that wasn't true for Spider Cave. Well, you have to realize that this level is far less difficult than Spider Cave (far fewer instant death spots, that's for sure), and that I haphazardly managed to find a fairly efficient route through Snowy Mountain while my route through Spider Cave was, by contrast, very scattershot. Even so, dealing with Snowy Mountain unlocks a bit of content in Spider Cave and the Mountain Pass, so I think it still almost evens out in the end.
This level also contains another (and the final) Flut Flut sequence, but it's even shorter than the offering in Boggy Swamp. I really feel the capabilities of the Flut Flut were squandered, as you barely ever have enough time to use it. Altogether, you could probably get through the entire game's Flut Flut exclusive content in three minutes or less. Kind of sad, don't you think?
If you're having trouble with the swing bars inside the fortress (I know I did; a surprising amount of cut footage was just me reattempting those swings), make sure you only jump once Jak is past the bottom of his swing arc. If you don't, you can easily end up repeatedly falling straight down instead of swinging forward like you actually want.
8:24 - Light as air. I find that glitch useful, but slightly creepy.
Funny thing is, the opened Yellow Eco vent is supposed to make the spider nest sequence easier, but I really think it actually makes things harder as it seems you can attack in a wider arc (if not faster) when you're not charged with Yellow Eco.
Besides nabbing a fairly hidden Power Cell after uncapping the Yellow Eco vents, it's nice to be able to blast away all those annoying instant kill explosive barrels in the Mountain Pass this time around.