Resourceful Rat's Lair (2024)

The Resourceful Rat's Lair (only referred to in-game as ???) is a secret chamber in The Gungeon, accessed through a hidden passage found in the Black Powder Mine in Enter the Gungeon. As the name suggests, it is the domicile of the Resourceful Rat and as such, nearly all floor features are themed around him. This includes the map only showing an animation of him holding a piece of cheese on a fishing rod and even the loading screen when entering the chamber.

Throughout the chamber, the player will encounter numerous rats holding candles. While these rats are harmless under normal circ*mstances, dying instantly upon player contact and occasionally yielding money, they can be jammed if the player has any curse, which will cause them to deal contact damage.

Like Bullet Hell this floor features no shops and no chest rooms (Unless one counts the reward room after beating the boss).

This chamber requires at least one key, two blanks, and the Gnawed Key to enter. The regular key can be substituted for key replacement items such as the Shelleton Key, AKEY-47, or Trusty Lockpicks, but the Gnawed Key cannot. If the Bullet That Can Kill The Past has been constructed, one random combat room in the Black Powder Mine will contain a hidden trapdoor which must be cleared off by walking over it, with goop, or with a blank.
The room containing the trapdoor is marked by the presence of three harmless rats.

Main Page: Black Powder Mine#Rat Room

Layout

The Resourceful Rat's Lair has the most unusual generation of any chamber in the Gungeon. It does not have a Shop, or an Elevator Maintenance Room, and no Chest rooms, NPC rooms, Shrine rooms, or miscellaneous random rooms can appear here.

Explosive Barrels, Tables, Coffins, and web goop are strewn about this chamber seemingly at random.

Points of Interest

• Entrance
• Maze
• Final Room
• Reward Room
• Baby Dragun
• Exit Elevators

Entrance

The entrance to the floor consists of a small T-shaped room with one exit to the east, leading to a circular room with a large pit in the center, and a Upon entering the floor, the player must fall down the hole in the room to the right to enter the maze. A small breakable wooden sign neat the top of the pit bears a downwards facing arrow, beckoning the player to jump in.

These rooms contain various harmless candle rat enemies, which wander aimlessly providing light with the candles on their heads. These rats may drop when killed, so it is advised to kill them. These rats may also be jammed, in which case they will deal contact damage when touched, but will still not hunt down the player.

Maze

The main layout of the Resourceful Rat's Lair consists almost entirely of a giant maze. After descending into the maze via the entryway pit, the player will arrive in a large, empty, rounded room with exits to the north, south, east, and west. Taking any of these exits will lead to a random combat room of similar dimensions, also containing exits in all four cardinal directions.

In order to reach the boss room of this chamber, the player must take the correct exits six times in a row. The clues to this secret route through the maze can be found in the six Infuriating Notes in the Ammonomicon.

Each note ends with a piece of cheese pointing in a specific direction, and the six directions are in order of the six notes in the Ammonomicon. If the directions are successfully followed in order, the player will reach the final room of the maze.
If the player does not follow the directions correctly, they will inevitably arrive in an elevator room, containing an elevator leading to the Hollow.

Notes

• The player must take the exact route detailed in the Infuriating Notes. Attempt to take alternate paths which should logically result in reaching the same endpoint will result in arriving at the elevator exit room.
• The route through the maze is different for every installation of Enter the Gungeon.
  • Different save files on the same installation of Enter the Gungeon will have the same path through the Rat Lair, meaning that a player can memorise their rat maze path, and immediately access the Resourceful Rat on a new save file without collecting all the Infuriating Notes.
  • Possible Bug In the Nintendo Switch version of Enter the Gungeon, the path through the maze is always the same for every copy, being down, right, down, up, down, up. This is not the case for other console releases of the game.
• The route through the maze does not change on future runs, and can be memorised.
• Bug If the player has the Bloodied Scarf, it is possible to teleport past the trigger that registers that the player has entered a Maze Room, allowing the player to wander around in darkness and potentially softlock the game.

Final Room

The final room of the maze is the same shape as all others, but contains only a single exit to the north, leading to the boss foyer for the Resourceful Rat. This room always contains two Ammo pickups and two full heart pickups.

Notes

• If the player is at full health, they can walk into the heart pickups to nudge them around. While this process is tedious, this can be used to nudge both hearts up into the boss foyer and into the Resourceful Rat's bossroom. Since the player cannot leave the boss room after defeating the first phase of the Rat, this is the only way to heal up using these hearts in between phases.

Reward Room

After defeating the Resourceful Rat, a large hole is blown into the center of the bossroom. The player must throw themselves down it, resulting in them being taken to the reward room.

This room contains eight golden item pedestals, in total sporting 2 keys, a Glass Guon Stone, a Blank, a full heart, a piece of Armor, an Ammo box, and a Spread Ammo box. In addition, near the top of the room there are four raised daises, each supporting a large Rat Chest. This is the only location where Rat Chests can appear.
The Rat Keys dropped by the Resourceful Rat during the Punch Out phase of his bossfight are necessary to open these chests, which always contain the same four items in random order, Elimentaler, Partially-Eaten Cheese, Resourceful Sack, and Rat Boots.

This room contains a single regular exit, leading to the Exit Elevators, as well as a secret wall concealing the Serpent room.

Notes

• If the player has the Mimic Tooth Necklace, it will not affect Rat Chests, however a unique NPC, the Union Mimic, will appear in this room to offer an explanation for this absence.
• AKEY-47 and Shelleton Key do not work to open Rat Chests, however Trusty Lockpicks and Drill can.
• Rat Chests can secretly be large, exceptionally strong Mimics.
• If the player already has one of the items that the Rat Chest would normally drop, it will instead drop a random tier item or gun.
  • This does not apply if the chest in question is a Mimic, or if the chest's contents are revealed, making it possible to obtain multiple Rat Boots. Other duplicates will simply disappear upon pickup, however.

Serpent Room

Main Page: Serpent
A small secret room off the main reward room, contining two locked gates and the Serpent NPC. The locked gates in this room must be opened with Rat Keys dropped by the Resourceful Rat. The Serpent can be fed guns, items, and the corpse of the Resourceful Rat by dropping them near it. After feeding the Serpent four different items, it will begin to orbit the player.

Feeding this serpent is a necessary step in fighting the Advanced Dragun.

Notes

• While this room contains two locked doors, passive items can be thrown through these doors. Unlocking only the first door allows the player to get close enough to toss items to the Serpent, saving a rat key.
• Bug If the player has the Bloodied Scarf, they can teleport past the secret wall obscuring the Serpent room without opening it. While this provides free access to the room, it does not reveal the room, forcing the player to navigate blind.
  • The player can also use the Bloodied Scarf to teleport past the rat locks which prevent access to the serpent, avoiding the need to spend a key.
  • If the player feeds the Bloodied Scarf to the Serpent after having teleported in this way, it is impossible to exit.

Exit Elevators

The exit to the Resourceful Rat's Lair consists of two elevator rooms connected to the Reward Room by an empty T-junction room. The left elevator costs nothing to access, and leads to the Hollow, while the second elevator is locked behind another Rat Key, and takes the player to the Forge.
Because this room contains two exit elevators, it contains two instances of the Save Button NPC.

Notes

• If the player has the Bloodied Scarf, they can teleport past the lock which prevents access to the Forge elevator without opening it, saving a rat key.

Boss

Enemies

Click expand to view the Resourceful Rat's Lair enemy table.

Rooms

• 2 random Shotgun Kin variants and 1 Mutant Shotgun Kin (all 3 being jammed) guarding an Ammomancer.
• 2 Lead Maidens.
• 2 Chance Kin accompanied by a player-seeking Dead Blow.
• 1 of each Shotgun Kin variant (excluding Executioners and Shotgrubs), a Shotgat and a Creech. Following this either when all enemies are slain or nearly all, a Jamerlengo appears.
• A jammed Chancebulon. This wave is followed by another jammed Chancebulon together with 2 regular Chancebulons.
• An on-spawning army of Rat minions.
• A horde of Spents together with a Gunreaper. After a fair few are slain, 2 Skullets and a Jammomancer join the fight.
• An empty room.
• 2 Shelletons.
• 2 Phaser Spiders.
• 2 Chancebulons and a Misfire Beast.
• 2 Pinhead, 1 Killithid and 1 Cubulon.

Related Unlocks

• Weird Egg - Enter the Resourceful Rat's Lair for the first time.
• Boxing Glove, Ring of the Resourceful Rat - Defeat the first two phases of the Resourceful Rat.
• Elimentaler, Partially-Eaten Cheese, Resourceful Sack, Rat Boots - Open Rat Chests after defeating the Resourceful Rat.

Notes

• The chance of naviagating the maze with zero Infuriating Notes discovered is 1 in 4096 or about a 0.02%.
• Despite there being no usable map in this chamber, the boss entrance still has a teleporter.
• The Resourceful Rat's throne rests upon a pile of stolen items, some of which are discernible, including 1 Coin Crown, 2 Boomerangs, 2 Boxes, 4 Ser Junkans, 1 Map, 2 Bottles, 1 Ammo Belt, 1 Yari Launcher 1 Ceremonial Sword, 2 Supply Drops (Using an older, unused sprite), 2 Mortars, and 2 old unused versions of the Ammo pickup.
  • The throne itself is ascended by stairs made of 24 Ammo pickups.
• The Resourceful Rat will not steal items left on the ground on this floor. However, since rooms cannot be re-entered once left, this is only observable when using items that transport the player back to the beginning of the chamber, such as Gun Soul.
• Bug If the player has flight when entering the Resourceful Rat's Lair, the loading screen will be the default loading screen instead of the rat variant.

See also

• Chambers