Sorry about the huge text xD, maybe I should change the stage names from stage # to their actual names, but hey, I'm lazy for the moment.
This walkthrough is for people who are having trouble finishing Heart of Ice. I don't know where all the secret things of secretness are (I do have 5 but I couldn't refind the locations lol xD), so if you do, tell me.
Though the game is pretty simple to play, I'll write a walkthrough about it because I want to >:)
Start a new game, then watch the cutscene.

IF YOU DIDN'T READ WHAT'S ABOVE THIS LINE, I'LL SUM IT UP FOR YOU. I KNOW THIS DAMN GAME IS FUCKING EASY AND SIMPLE, BUT I DON'T GIVE A SHIT BECAUSE I DAMN FELT LIKE MAKING A WALKTHROUGH AND THIS WAS THE FIRST GAME I SAW AND YOU AREN'T ABLE TO DO ANYTHING ABOUT IT, HAH. (It may even be helpful to someone, couldn't it?)
Now let's begin with the walkthrough, shall we? :P

Stage 1: keep walking to the right, pretty straightforward level, you'll get a short tutorial on how to play. Oh, and dodge the crystals, they hurt.
Stage 2: Walk to the right, still dodging the crystal things and smash the crates open to continue to the next stage.
Stage 3: Take out the Ossicles (that's how the eyes in a shell are called) with 2 quick strikes, congratulations, you have totally knocked the sense out of your first bug. When you reach the bouncy, keep walking "through" the wall. You will see a Ossicle and a chest at the back. Kill the Ossicle, kick the crate, and pick up the Mysterious blahblahblah (secret item 1). after that, go up the bouncies and walk to the next stage.
Stage 4: Don't keep the right button pressed when going from stage 3 to 4, for you'll run straight into either an Ossicle or a toxic gas vent. Kill the Ossicle, jump over the vent when it's not spewing toxic gas. You'll see your next opponent, a Gyrid. Don't charge at him, wait for him to have his spikes in, then beat him up. Go over the four vents, kill the Gyrid, jump over the bouncies (watch out for the garbage falling down) and proceed.
Stage 5: There's a vent at the beginning, jump over it, kill the Gyrid, you will then see another type of enemy, a Spritz. He shoots bullets, so watch out. If you don't want to take damage, watch carefully how the bullet flies, you will see a place where you won't get hit, from there, you can easily kill him. Jump to the blocks of ice in the water (there's a message on a stone before the jump) kill the enemies and jump down in the tunnel at the end.
Stage 6: Just take the health pack and jump down again.
Stage 7: Go to the left, jumping over the blocks of ice until you reach a boat, get in it and go all the way to the right.
Stage 8: If you're not good at timing, you can just keep the right button pressed and get there alive, though you will have lost a lot of health. If you are however, try to get close to the spike balls at the ceiling, then get under it when they have fallen. They fall very close to your boat though, so you may want to consider rushing. (your health regenerates over time)
Stage 9: go to the right until you reach a landing place for your boat. Step out of the boat, and jump on the bouncy to your right, then on the other bouncies above, while killing all the enemies. after the bouncies, jump down, kill the Spritz, and activate the switch (you may want to take the healthpack if you're injured). Then, go all the way back to your boat and drive through the gate to the right.
STAGE 10: watch the cutscene and go left. Oh, and prepare for a boss fight ^^
Stage 11: Yay, a boss fight! Wait near the block of ice (it has to start shaking) until a cutscene initiates and you have to fight Tim the Frost Pirate. This is one of the easiest boss fights, so don't worry too much.

BOSS FIGHT: Tim the Frost Pirate
Phase 1: He'll start running at you, which means he will attack you (obviously). Don't worry though, he's a bit slow. When he's near you, run straight through him and attack his back 3 times. Repeat this the whole time.
Phase 2: He will jump at a side and start throwing bombs at you, the coward! Dodge the bombs, you can try to get really close to him and attack him, or he will jump away and start bombing somewhere else or running at you again.
Phase 3: He has 3 new attacks now. The first one looks just like the attack of Phase 1, except for the fact that he'll start whirling around and you won't be able to attack him. He'll only whirl when he's really close, so don't get fooled!
His second attack is when he starts to whirl around in the air, throwing bombs straight down. This is pretty easy to dodge if you just stand in between two bombs. His third attack is when he jumps up, but smashes down with his sword. Don't be close to him when that happens, you get hit easily from it. You will have a chance to hit him when his sword is 'stuck' in the ground.
Phase 4: He will have another attack, starting to shoot at you, bah! A bar will appear showing you when to jump. Jump when the pointer is in the green area.

After the boss battle, another cutscene will initiate and you'll be facing Tim with a ghost ship. This battle is even easier. He will have a long rowing paddle (which won't hurt you) and he will start poking the air and summoning 4 bombs. Just dodge those. Another attack is summoning ice spikes from the ground, just go to safe ground (you will see a blue layer of ice where the spikes will hit). the only chance to hit him is when he smashes the ground and summon shockwaves that you can jump over. He only takes about 10 hits.
When you've finally totally owned that boss, continue up the stairs.
Stage 12: Just get in the elevator and activate the lever.
Stage 13: You're in the elevator, no need to do anything, just watch the screen.
Stage 14: You will have lost about a quarter HP when you crashed, get off the elevator (jump to the grey rock). Then jump on the moving platforms (watch out, slippery road), and continue.
Stage 15: Jump on the moving platform, jumping over the obstacle. You will see an enemy running to you and launching a rocket, a Sentro-Bot. These are dangerous. Dodge the rocket, jump down over the next one he fires at you and hit him. Keep employing that strategy at the other Sentro's and you'll get there. The Sentro at the last moving platform doesn't need killing, just jump off the platform when it's up, and walk by him.
Stage 16: No need to kill any Sentro here, just jump on and to the platforms. When you don't see a platform to your right, just wait a while, then jump on it. Dodge the drills and proceed.
Stage 17: Who wants a roasting bath? Don't jump in the water, jump on the stone and wait until the Sentro stops electrocuting the water to go and take him out. You have to do this a few times. Kill the Sentro at the end (or don't) and continue.
Stage 18: Wait for your timing to kill the first Sentro, then continue, killing all the enemies on your way. Before the weird black bars, you will see a lever. Yes, I know it's harder now, but the door won't open otherwise. Go through the black bars, dodging the red dots, and continue.
Stage 19: Go to the right, activate the lever, go back to the left. Go up the fan, kill the Sentro, go to the right, wait for the bar to appear before you jump on it and jump on the fan, then go to the left over the bars. If you can't manage to get over without falling, watch how fast the bars switch positions. Pull the lever on the left, then go up the fan that activated. Go to the left, up the bars and the fan to reach yet another lever, pull it. After that, go all the way to the right and go up the fan, killing the Sentro again. Then, go up to the left. If you want the fourth secret thing, keep going left and fall down on the platform above where you pulled that lever to get the defending blahblahblah thing. Otherwise, go to the right and continue through the door.
Stage 20: This is one of the shooter parts of the game. get your mouse ready and pull the lever just after the gun. Then, quickly get in the gun and start shooting at the Destro-bots who appear. Try and keep em all shot because after 2 seconds near the generator, they'll attack it. The ones who jump to the left of the generator mostly need one shot per 2 seconds for all of em, while the right needs some time since you are not right under them. Try and time it carefully, but keep the mouse pressed anyway. Once you got rid of the robots, the gate will be open and you can go on.
Stage 21: Jeez, long pipe. Don't let the boringness and seemingly neverending path get you frustrated, it'll end. At the end, fall down and prepare for a boss fight.
Stage 22: Watch the cutscene and pwn that lunatic.

BOSS FIGHT: Ishmael the Cold Lich
Phase 1: Easy phase, make sure you stand in an angle so that Ishmael's electricity bolt hits the panels on the left and right of the gun. Watch the charge bar below the gun, when it's filled, get in it and start shooting. Don't get in before it's charged though, or you'll be hit with an attack. Fire him up for a while until he makes a force field around him and starts counting down (could be three two one but he says two two one a lot too for some reason). When he starts counting down, get out of the area of the gun, it'll be blasted and you'll have to charge it again.
Phase 2: He's gotten smart, fast thinking for a psychich (lol). He'll send bolts of... uh... something other than electricity around the sides to you, just jump over them, but remain in an angle so that a panel stands between you and Ishmael. He'll sometimes fire a bolt.
Phase 3: He'll start summoning balls of pure don't-know-what at you, dodge these whenever you can, they hit alot. Keep firing him up with the gun as soon as it's charged.
Phase 4: If you're not good at playing with inverted controls, this phase will be hell for you, he'll flip the screen, so left is right and right is left, that will stay for about 20 seconds. Keep dodging the balls of doom and firing and eventually he'll get pwned.

When he's defeated, a cutscene will initiate and you can call yoursedlf victorious against another boss.

Stage 23: If you want a secret item, don't get off the elevator, just pull the lever and go up the roof on the stage there. You will find the loyal flag blahblahblah. This is the sixth secret item. After that, go on down the roof and talk to tim to unlock a boss fight. Then jump off the building at the right.
Stage 24: jump down, you will face the most annoying normal enemy of the game: the ninja. these guys are quick and sturdy and jump when you hit them, so practice a bit killing them before you go on. You can jump when they do to do an aerial attack which they can't dodge, or you can wait until they perform an attack to get at their rear and bash em up. After you got them all proceed up the bouncing platform.
Stage 25: First of all, go down and pull the lever on the right, ignoring or killing all ninja's. Then, go back up and jump over the stone heads to the last one without fully lowering one. Lower the last one, jump down, go back up and repeat it with the second last, third last, to first. Kill any air rodents (the birds), they shouldn't be much of a problem. Then, proceed through the gate.
Stage 26: A wall of a certain doom, yay, every game has one :P. Jump down and start running forward. There will be sword obstacles. Just watch the pattern and get through it as fast as possible. After a few sword traps, you'll find a snow path, you're there. Continue on through the pathway.
Stage 27: First, run to the left. The ninja's always keep respawning so don't bother killing those unless they're an immediate threat. At the end, you'll see a switch, flip it. Then go to the middle of the map, go up the fan to the big hand and flip the switch there, then run to the right and flip the switch there. After that, go all the way left, there should be a tunnel now.
Stage 28: Ooooh, very special stage. go to the left, pull the lever and dodge the boulders coming at you. After a while, the watcher will pop up and start shooting you with pink stuff and a minigun.stay away from the pink stuff, it hurts. When he takes out his minigun start running away from it, simple enough. Don't try to attack him, he can't be harmed. After a while he'll leave and you'll have to dodge boulders again. When it all stops, continue to the right.
Stage 29: Just get to the end, kill the ninja's. Near the edge of the stage there's a bounce pad, step on it and as soon as you're launched, fly to the right and pull the lever. Then, continue through the gate and prepare for your last battle! (Last official battle, of course)
Stage 30: Walk towards the middle and watch the cutscene as you approach the shiny thing. After the cutscene use the broken shiny thing to jump up high to the platform above your right. Prepare for the hardest official boss battle in the game.

BOSS FIGHT: The Watcher
This boss may be a bit tough when you're playing on a laptop (like me). You may want to use a mouse for this.

Fight nr. 1:
Phase 1: No watcher to be found, just dodge the rocks.
Phase 2: Watcher's arrived, and he wants to play. Dodge his plasma bolts (the purple thingies) while keeping him pinned down with your gun. He'll also shoot at you. The best strategy is to keep targeting him while flying around in circles. When he's at half HP, he'll start going berserk, don't worry about that, just keep making geometric shapes with yer plane and shoot the hell out of him.
A cutscene will initiate and you'll be facing The Watcher with all of his powers, The Ascendant.

Fight nr. 2:
Phase 1: He will summon static energy blasts near you, when you see a small light growing stronger near you, get out of the range. Safest is to keep some distance till you found out what that range is.
Phase 2: He will be summoning a lot more energy blasts, just keep dodging them. Eventually, he'll generate a yellow force field. He's invincible for now. He'll just keep smiting you with some bolts and really big globes of death. Try to keep at the low section of the screen. When he throws the globes at you, get to the upper side as soon as possible to dodge the first one and to another direction for the others. After that his force field will weaken and fade, and you can start shooting again.
Phase 3: That's it, no cookies for you! He will start summoning purple force fields. When he does, get to the middle of the screen as soon as possible, for he'll summon some electricity things to lighten up your day. Try to stay away from them, they hit a lot. When one's at the middle of the screen when it comes from below, it'll start turning, be prepared for that.
Phase 4: The Ascendant got thirsty from the battle and while you weren't looking, he drank some RedBull, now he has wings. Don't stare at em though, just ignore em and keep firing at the dude. He'll also call in laser strikes. If you see a line of light, you know what to do. (get away from it)
Once again, a cutscene will initiate. It ain't over yet though, get ready for yet another Boss fight.

Fight nr. 3:
Phase 1: The Fallen arose and ye'll have to fight him. He'll jump to a corner, then shoot bolts from his swords. If you're fast enough, run under the bolts and hit him in the face while he's firing, makes you kill him faster. If you're lazy, dodge the bolts until he takes a breather, then hit him in the face.
Phase 2: He'll charge forward on the big platform, try to jump over him or just stay on one of the smaller platforms.
Phase 3: He'll imitate a vacuum cleaner, run away from him while he does. He'll do all the previous moves too.
After the battle, you'll be forced to watch yet another cutscene.
After the cutscene, walk to the left, over the blocks of ice, and watch the cutscene at the end.
Then, you'll suddenly be in a pixel world. Stand still before any spike, then continue, in the screen with the pirate, get up, smash the switch thing and run away from the boulder. I won't go into too much details with this level.
After the pixel world, you'll have to fight The Watcher again, but this time it's really easy;
Phase 1: The Watcher will just go to you and punch you, just jump over him and attack him from behind.
Phase 2: The Watcher will start powering up his punches, just keep attacking him from behind.
Phase 3: The Watcher will start walking around. You know the drill.
Phase 4: He'll get smart now. Try to catch on his timing between punches, getting behind him won't work anymore, he'll kick you. Just beat him up between two punches.
Phase 5: He starts running around like mad. makes it easier though.
The HP bar will disappear and when it does, keep mashing the punch button at him. eventually you'll see parts of reality and thoughts coming through, and eventally, you'll get... Another cutscene!
After that cutscene, the game will end and you will have finished it, congrats ^^.
EXCEPT...
If you had 5 secret items.

Boss Fight omgwtfbbq: Vercingetorix.
Phase 1: Vercingetorix will make a shockwave that goes to both sides. Just jump over that, can't be hard. After that, he'll activate rocket launchers, try and run one bit at a time so the rockets "nearly" hit you but not explode. Then, he'll have to rest, hit the dragon-like thing, he'll lose health. After a while, you'll see him getting ready for a shockwave. Just stand on the stone to your left and it won't hit you.
Phase 2: At about 50% of his health, the elevator will go up and you'll be facing the upper part. When the knight strikes the ground, rays of light will start appearing, stay away from them. Then the lasers will fire a certain (pink) Area, just stay out of that range too. Basically, it's best to stay not in the middle but near it, so you can run to both possible safe zones. After that, the head will start firing rocks, run like hell to dodge and whack the one that gets stuck so it hits the boss, repeat this.

Now you have TRULY completed the game, congratulations once more kthxbai ^^

Any questions, strategies or other suggestions? feel free to pm me or leave a comment ^^