This area can be accessed in 1-1, 1-2, or 1-3.

Simply ignore most of the enemies (kill only one or two), open all chests (including rad canisters and Portal Strike Ammo containers), and Big Bandit will appear. Kill him AS FAST AS POSSIBLE, and you'll be on your way to the Oasis.

Inside the Oasis, schools of Bonefish and some angry hermit crabs will be after you. Bonefish are essentially Rats, and Hermit Crabs are just faster, weaker Scorpions.

As soon as you complete the level, you will be transported to Big Dog! Be prepared.

NOTE: The fish skull prop in every level will tell you if you've killed too many enemies to go to Oasis or not. If the mouth is open, you're good, if the mouth is closed, try again.

Go to the sewers, then bust open the one manhole in the area with an explosive weapon, easy as that.

Inside, there will be four [teenage] mutant [ninja] turtles, and a single rat. Kill all of them and you'll be on your way to the Scrapyard.

If you get here as Eyes, you will unlock his B-Skin.

NOTE: The weapon you get in the weapon chest in the Sewers will usually be the same weapon as the weapon in the weapon chest in the Pizza Sewers! WEAPON!

Get a screwdriver from a weapon chest. Take it all the way to 3-1, and find a broken-down, golden car. Hit the it with the screwdriver ONCE and press E on the car. You are now in Y.V.'s Mansion, and if this is you're first time here, welcome to Venuz! You can now play as Y.V. himself.

Alternatively, if you're a madman while looping (or if you're extremely lucky as Robot), you can also repair the car with an energy screwdriver. Be warned, because of how much damage the energy screwdriver does, it is likely to blow up the car if the car has taken damage. It is guaranteed to explode if you have Laser Brain.

Patrolling the area will be various enemies from Gun Godz; Mole Fish and Sarges, Jocks, Fireballers and their super variation. Mole Fish are really just Bandits, Sarges are just alligators, Jocks fire missiles at you (which can be run-ending), Fireballers and Super Fireballers just shoot at you. Be warned, Super Fireballers can turn the game in to a bullet hell in the blink of an eye!

Somewhere in the level, there will be a Golden Weapon Chest. Opening this gives you a random Golden Weapon (minus the ones you obtain on loop-only, unless you are looping), which can be chosen as a starting weapon for your character on the main menu screen as soon as you go through a portal holding it.

WARNING: Do not go for this secret area unless you are a pro. Don't be a hero!

The way you get to the Cursed Crystal Caves is simple; obtain a Cursed Weapon (which has a 1/7 chance of spawning if you have a crown), and beat Big Dog. You are now in one of the hardest areas of the game.

The level will be packed to the brim with Cursed Crystal Spiders with a 25% chance of splitting in to two more Cursed Crystal Spiders, which do the same thing. There will also be a hefty handful of Cursed Laser Crystals, randomly teleporting a short distance, which can result in cheap telefrags.

After clearing through the horde of enemies, there will be a Cursed Large Weapon Chest, characterized by its purple tint and cursed crystals growing out of it. When you open it, you will be presented with three cursed weapons, all of which can be weapons from four difficulties higher!

If you get to here as Crystal, you will unlock her B-Skin.

WARNING: Do not go for this secret area unless you are a pro. Don't be a hero!

Just obtain Last Wish before 5-1, and get to 5-1. Near your spawn, there will be a large, frozen corpse flower. "Feed" it 4 HP, and a portal will open, killing everything in the area, and transporting you to the Jungle. Upon spawning, you will unlock Chicken.

From the start, hordes of upgraded Bandits will swarm you if you do not find cover, each of them equipped with a Pop Gun! Giant Flies idly float by, shooting Maggots at you if you get in their line of sight. They will also explode in to maggots upon death. If you so happen to touch them, you will take an absurd 5 damage. Worst of all, Assassins hide in bushes, and have zero tolerance for visitors. They react twice as fast and can hit you in a fraction of a second of you waking them up.

Assuming you survive through all of this (you ultimate beast), you will be teleported to 5-3. Prepare for Lil' Hunter!

NOTE: Y.V.'s Crib can only be accessed by Y.V.

Simply play through the game far enough until you get your ultra mutation as Y.V. Choose either of them, depending on whether you prefer more damage output or more damage output, and you'll be on your way.

Inside of Y.V.'s Crib, there will be no enemies. Just a garage full of golden cars, and Y.V.'s spherical cousin, Yung Cuz (otherwise known as Y.C.), who will be playing video games on a giant golden TV while eating triangular chips. Activating the airhorn makes him cheer, and destroying the TV (which has 1000 HP) will make him cry. Doing the former after the latter will still make him cheer anyway. To the left and right of him, there will be two giant weapon chests, each containing 25 weapons! If you have a bad weapon loadout, this is the surefire place to go. To exit, you simply must press E on one of the golden cars, and you'll enter the next level.

If you happen to have the Crown of Love, the two giant weapon chests will turn in to giant ammo chests! Each will spill out and flood the room with about 50 mini ammo boxes in total.

If you took Open Mind as a mutation earlier, then congratulations! Instead of the normal two giant weapon chests, you'll now have three! Have fun with 75 forever-dancing guns to choose from!

WARNING: Do not go for this secret area unless you are a super-duper pro. DON'T BE A HERO!!

The I.D.P.D. Headquarters is a loop-exclusive secret area that can only be entered by pressing the 'E' key on the back of an I.D.P.D. Van while it is moving or unloading troops. If the van is lying dormant and no more troops are coming out, you've missed your chance.

Upon entering the area, you will be dropped in to an alternate universe where the apocalypse didn't happen. Shrubs are prominent, and everything is sparkly clean. Large troops of I.D.P.D. roam the halls of the establishment, including Elite I.D.P.D! Even though this is their headquarters, the I.D.P.D. will still crash vans in to the area to try and stop you. The area is three levels long, with the final level housing an alternative final boss.

This final boss is the Captain of the I.D.P.D. She will idly sit at her desk until damaged. Upon being hit, the fight will begin. She will encase herself in blue energy, taking the shape of a muscly blue ball. She has three different attacks; charging at you, not unlike Big Bandit (though it happens much quicker), teleporting and shooting giant blue balls (not unlike the Throne), and turning the game in to Touhou with the amount of projectiles she fires. She has around the same amount of health as the Throne, and is a very difficult boss.

Upon defeating the Captain, you will beat the game and are able to watch a second ending.

If you defeat her as Rogue, you will unlock her B-Skin.