There are a total of ten weapons, but you may carry only seven at a time--so choose wisely!
Warning: Once you exchange a weapon, you typically cannot trade it back, so choose wisely.
 Polar Star
Location: Obtained from the hermit's shack in the First Cave.
- Level 1 - Shoots a single bullet. Deals 1 damage.
- Level 2 - Shoots a double bullet that fly slightly farther. Deals 2 damage.
- Level 3 - Shoots a larger bullet that flies farther than the other levels. Deals 4 damage.
Notes: This is the basic weapon, which can be traded/upgraded further in the game.
 Missile Launcher
Location: You can get this weapon in the Egg Observation Room. If you skip the chest in the Egg Observation Room, it will appear in any chest that would normally upgrade the amount of missiles you can carry.
- Level 1 - Launches a small missile that does moderate damage. Deals 8 damage.
- Level 2 - Launches a large, very fast missile that does a high amount of damage. Deals 15 damage.
- Level 3 - Launches three small missiles at once, while still only using one ammo. Deals 8 damage each (24 total).
Notes: A very powerful and useful weapon, but its ammo is extremely limited. Can be upgraded in the Boulder Chamber. Other than its upgraded counterpart and the Blade level 3, this is the only weapon in the game with a blast radius.
Location: Found in Santa's house in Grasstown after letting him into his house.
- Level 1 - Shoots a single fireball that deals 4 damage (maximum 2 fireballs).
- Level 2 - Shoots an orange fireball that deals 6 damage (maximum 3 fireballs).
- Level 3 - Shoots a blue fireball that deals 6 damage (maximum 4 fireballs).
Notes: This one is good for shooting up hills or attacking enemies below, but for straight shots and airborne foes it doesn't do a lot of good. Also, this weapon will plow through weaker enemies, only dealing half if its damage to the enemy (if the enemy is destroyed by this much damage), then continuing until its range limit is reached or it hits another enemy.
Location: Use the Jellyfish Juice on the fireplace inside the Assembly Hall to get this weapon.
- Level 1 - Short range, deals 1 damage, and shots hang in the air a bit. Must tap the fire button.
- Level 2 - Range nearly doubles, deals 2 damage, and you can hold the fire button (rapid fire).
- Level 3 - Hold the fire button to summon bubbles. Release it to send them all in whatever direction you're aiming to make a powerful shotgun-type blast (3 damage per shot). There is a limit to how many bubbles you can summon at once - when this limit is reached, the bubbles will start shooting forward by themselves. You can also use the swarm of bubbles as a sort of shield that destroys weak enemies on contact (note that if the bubbles get hit before you fire them, they only deal 2 damage). If there are more enemies than bubbles, they can get around the shield, so be careful.
Notes: It is very weak at first, but leveling it up gets you a fairly powerful weapon. Due to the way the bubbles move around you, this weapon works best against flying enemies. The bubble "shield" is also good for blocking projectiles.
 Machine Gun
Location: Curly gives this to you in exchange for your Polar Star after you defeat her in the Sand Zone. Warning: if exchanged, you will miss the opportunity to gain the Snake. It can also prevent you from getting the Spur. The Spur is much more powerful than the Machine Gun and useful for later bosses.
- Level 1: Fires small bullets that deal 2 damage each.
- Level 2: Fires larger bullets that deal 4 damage each.
- Level 3: Fires very large bullets that deal 6 damage each. In addition, this level adds recoil to the weapon when you shoot. This effect can be used to hover in the air by shooting downwards. It can also increase fall speed when shooting upwards while falling, but that has very little use.
Notes: It fires quickly, but its ammo is limited and must recharge. Also, you can get the Turbocharger from the Labyrinth shop to improve the recharge rate of the weapon.
Location: King gives it to you as memento after you defeat Enraged Tokoro.
This weapon's only downfall is that you can only use one at a time, however, if you are close enough and not using a level three weapon, you can still hit the enemy repeatedly, dealing lots of damage. The level 2 blade has the highest damage output rate of any weapon in the game, though it can be difficult to use in some circumstances. All in all, the level 3 version is better for most situations, though the damage output of the level 2 makes it very useful in a pinch. Remember though, that this requires getting very close to your enemy, so watch out and don't get slaughtered.
- Level 1: Throws a small sword that deals 15 damage. Has medium range, but can only fire one blade at a time.
- Level 2: Throws a larger sword which has a shorter range, but deals 18 damage and can be fired immediately after landing a hit, so button mashing makes it very effective at killing large groups and, notably, at killing Monster X.
- Level 3: Summons King's soul that flies a short distance in a straight line. Small slash-like projectiles appear randomly around King's soul; if these touch enemies, it deals a small amount of damage. If King's soul touches an enemy, it will be struck many times repeatedly and then attack other enemies nearby. The amount of damage it deals depends on the enemy; it can often kill small enemies in one shot. Note: You automatically go to max when you reach level three, meaning you will downgrade if you get hit even once. If you want to keep using King, don't get hit.
Location: The shopkeeper in the Labyrinth Shop will combine your Polar Star and Fireball weapons to make this powerful weapon.
- Level 1 - As many shots as you can shoot, fires through walls. Deals 4 damage.
- Level 2 - Moves like a snake, goes through walls. Deals 6 damage.
- Level 3 - Longer range, still goes through walls. Deals 8 damage, and 4 shots allowed at once.
Notes: It is the only weapon that can shoot through walls. It can be very useful in Hell speedruns, by activating time delayed events early.
Warning: If you collected the Machine Gun, you won't get this weapon at any time in the game. If you got the Booster 0.8 before getting the Snake, you will no longer be able to retrieve it after defeating the Core. Otherwise, you are given a choice to either get the Snake or the Spur; you cannot retrieve both.
Location: Trade the Polar Star back to the Hermit Gunsmith to get this weapon. Unlike other weapons, the Spur doesn't use exp. Rather, it relies on charged shots by holding down the fire button.
- Level 1 - Same shot as Polar Star level 3. (Without the 2-shot at a time limit.)
- Level 2 - Fires a thin laser. If it kills the enemy, then it will go through them. Deals 15 damage.
- Level 3 - Same as level 2, but it shoots two lasers. Deals 50 damage.
- Level Max - A powerful shot, wide angle laser that can destroy most enemies in one hit. It can deal up to 100 damage.
Notes: It is the most powerful weapon in the game, and is comparable to the Nemesis. If you have this item, you can go to the Labyrinth Shop to obtain the Whimsical Star, a small item that orbits and inflicts minor damage on enemies. Also note that because this weapon runs on exp, even though you charge it up, if you get hit, you lose some charge, and collecting exp will speed the charge up
Warning: If you collected the Machine Gun or the Snake, you won't get this weapon at any time in the game. If you got the Booster 0.8 instead of the 2.0, it becomes much harder to reach the cave to get the spur, but it can be done.
 Super Missile Launcher
Location: Found in the Boulder Chamber after defeating Balrog
- Level 1 - Launches a small Super missile that does moderate damage. Deals 3×5 (15) or 3×6 (18) damage, as it does multiple hits per shot.
- Level 2 - Launches a large Super missile that does a high amount of damage. Deals 3×9 (27) or 3×10 (30) damage, as it does multiple per shot. Two shots are allowed at once.
- Level 3 - Launches 3 small Super missiles at once, while still only consuming one ammo. It does 3×5×3 (45) or 3×6×3 (54) damage. Two shots are allowed at once.
Notes: Power levels are the same as the Missile Launcher, except they do much more damage and accelerate faster.
Location: Trade the blade to the Little Man in the door at the bottom of the Outer Wall.
- Level 1 - DON'T LEVEL UP! Great range (at least 1/2 of screen), incredible damage (12), and a slight plowing effect. Limit 2 shots on screen, but they travel fast. Curly uses this later.
- Level 2 - Again, don't level up! It gets worse. Damage is halved to 6 damage, although it's still a decent weapon. Range is about the same, limit 3 but they don't travel as fast.
- Level 3 - If you get to level 3, you can get hurt to go back to level 1. Worst weapon ever: it does 1 damage and has less range than the level 1 Polar Star (It fires ducks on wheels).
Notes: This is the only weapon in the game that gets weaker as it levels up. Also you may trade back this weapon for your blade. If you trade it back then the Blade will be level 1 and if you trade your Blade AGAIN for the Nemesis, it will be at level 1. It levels up with only one exp point, so avoid them or switch to a different weapon.
 Field Items
- Save Disk
- Server (Health Restore)
- Treasure Chest
- Single Heart
This Item, which can be gained from defeated enemies, will restore your health by 2 points.
- Multiple Hearts
This item, which can be gained from defeated enemies, will restore your health by 6 points.
- Heart Tank
- Energy (Small)
This item is dropped by defeated enemies and adds 1 experience point to your currently equipped weapon.
- Energy (Medium)
This item is dropped by defeated enemies and adds 5 experience points to your currently equipped weapon.
- Energy (Large)
This item is dropped by defeated enemies and adds 20 experience points to your currently equipped weapon.
- Energy Box
This item can be opened with a single shot from any weapon. When opened it releases varying amounts of energy.
- Arms Barrier
This item halves the amount of experience lost when you are hit. Located in the Labyrinth, above the physician.
Picking up this item will refill your missile supply by 1 missile. Works with both normal and super missiler
- Multiple Missiles
Picking up this item will refill your missile supply by 3 missiles. Works with both normal and super missiler
- Missile Powerup
- Super Missile Powerup
The exact same as the missile powerup, but the color is changed to reflect the color of the super missiles
 Event Items
These items are used in conjunction with the story or are just fun little secrets to find. Unlike other items, these ones can usually only be found once and in special scenes. There are two types of event items: Normal event items, which are found throughout any game and hard event items, which are only used when you are attempting to reach the hard ending. You must collect ALL hard event items to reach the hard ending.
 Normal Event Items
- Map System "So long as you retain your spirit of exploration, surely you shall find your way out. This I believe."
The map system can be accessed from the item menu or by pressing. Found in the Mimiga Village, it allows you to see the map layout of any area you are in. It's located on the ledge below where graveyard is, and above the shack.
- Silver Locket "A silver locket in the shape of a fish. From the condition it’s in, it looks like it’s been treasured for years."
Found in at the bottom of the Reservoir, this locket was a gift from Sue to Toroko as a symbol of their friendship. Toroko lost it and would really like it back.
- Arthur's Key "The key to Arthur’s house. It was hidden near Arthur’s gravestone."
- I.D. Card "An ID card found in Egg No. 06."
The I.D. card is found in Egg No. 006 and is used at the computer in Egg No. 001 to open the force field to reach Egg No. 00. There is no other purpose for it.
- Santa's Key "The key to Santa’s house."
Santa's Key is found in Grasstown, in an area a few screens from where you talk to him. It is pretty hard to miss, as it is surrounded by many enemies. Give it to Santa for him to open his house, which is required to get another item.
- Chaco's Lipstick "Red lipstick. It has no use."
This is the first extra item that you can get in the game. To get it, examine Chaco's fireplace the FIRST time you go into her house (Otherwise it will not work), then immediately go to sleep on her bed. When you wake up you will have it.
- Jellyfish Juice "A fluid that can quench fireplaces."
The jellyfish juice is one of the few event items that can be refilled as many times as you want. You can get it by defeating the large jellyfish in the area where you found Santa's key. It is used to put out fires.
- Rusty Key "A Rusty Key"
Given to you by a strange man stuck in a house in Grasstown. The rusty key doesn't open his door but it will open the door to the power generator room right below the cliff you used to drop into the area.
- Gum Key "A tag says Gum"
This item will be given to you by the same man who gave you the rusty key. He will only give this to you after you talk to the robot in the power generator room. It is used to unlock the door to the Gum Area.
- Gum Base "A clump of gum."
One of the items required for explosive, it is found in the chest in the Gum Area. A word or warning however, as opening the chest will initiate a boss fight with Balrog.
- Charcoal "Taken from a fireplace."
Another item required to make the bomb, this item can be gained by using jellyfish juice on Santa's fireplace. You don't have to talk to the robot before getting this item however, so you might want to get it before you go over the cliff.
- Explosive "An explosive for blowing up doors and such."
Once you get all the items, talk to the robot again and he will make you the explosive. You then use the explosive to blow up the door and free the man trapped inside the house.
- Curly's Underwear Retrieved from behind the wall. Yellow-green panties with a cute little insignia. They have no use."
Check the map in the back room where you first meet Curly to see the route for getting her underwear. Will unlock Curly Story mode in CaveStory+ after Warehouse fight.
- Alien Medal Engraved with a silhouette of an alien. It has no use. Obtained by defeating the reservoir boss (Ironhead) without taking damage.
- Booster 0.8 Received from the professor in the labyrinth, if you follow his downward path. Click jump two times to fly. Note: Unable to upgrade to Booster 2.0 on easy mode in Cave Story+.
 Hard Event Items
- Tow Rope "A tow rope for robots."
Found in the Core battle area. It's found in the lower right area of the room beside a square rock, and can only be picked up when not in combat and before you run out of air. The tow rope is used to save Curly after the battle with the Core. While you can pick it up after the battle, the flooded chamber makes it slightly harder to return to Curly. *NOTE* This can only be received if you don't have Booster 0.8.
- Booster 2.0 Received from the professor, if you didn't see him in the labyrinth. Press jump in mid-air along with a direction to instantly change direction of your flight. You can also conserve a bit of fuel by rapidly tapping jump. Must be equipped before use.
- Whimsical Star Received from the weapons shop in the Labyrinth if you go back with the spur. When equipped and when Energy is collected for a weapon that is at max level, or the Spur is fully charged, it releases three stars that sporadically fly around, inflicting 1 damage on contact to targets in a wide area (at most half the screen at times). If you get hit, the number of stars you have hovering around you is decreased by one.
- Nikumaru Counter Received from a side passage in Outer Wall. Used to unlock a new character on the title screen if you complete Sacred Ground (Hell) within six minutes.
- Iron Bond Received from Curly, after meeting her in the Plantation area and restoring her memory.
 Unobtainable Items
- Beast Fang: "You're not supposed to find this. How'd you do it?" The Beast Fang is an item that is located inside the block under the Heart Capsule in Yamashita Farm. It is impossible to get in-game and it's planned use is unknown. See the "Cheats" page for info on how to hack the item into your inventory.