From GameBrew

Last Updated2016/03/19
VersionRelease 7

EUCLIOD is a Bullet Hell Homebrew for the 3DS.


Available in 3DSX and CIA versions. Despite the CIA version being a more recent release (r7), the 3DSX version is still superior (r6.1).

  • 3DSX - Use the .3dsx provided with the Homebrew Launcher.
  • CIA - Install the .cia with the CIA manager of your choice (no sound, no custom levels and settings are not saved).

User guide

The game has 6 enemies, 3 bosses with multiple phases, and 5 different weapons.

It is a bullet hell game: so you get one life, and a tiny hitbox.

You can remap the Fire and Focus controls to A, B, X, Y, L, R, ZL, or ZR in the options menu if you don't like the default.

Custom level (3DSX)

  • The game will load from any level named correctly. levelx.dat should be the filename where x is the number with no spacers.
  • The game will state invalid if the file does not exist or if the file does not have "v001" on the first line.
  • The game will likely crash if you have both these but the syntax in the file is incorrect.
v001 //add this to the start of every level you make, it won't start without it
  • Every line has to be exactly 20 characters long, in this exact format.
  • The first 6-digit number is the frame the enemy spawns, if you're not lagging this should be 60 per second.
  • The second cell is the enemy that's spawning.
    • "en01" (Fighter) is the enemy that targets you with bullets.
    • "en02" (Bomber) is the enemy that sits still and shoots slow bullets directly downwards.
    • "en03" (Strafer) is the sliding enemy that lays down a curtain.
    • "en04" (Helix) is the enemy that shoots a helix of bullets and diagonal shots alternatively.
    • "en05" (Kamikaze) is a slow moving enemy that proceeds down the screen and then detonates into a ring of bullets if not destroyed.
    • "en06" (Asteroid) is a large object that soaks up player shots. Graphic and direction is deterministic based on the frame it was spawned in.
    • "en07" (Odin) individual mob. Untested.
    • "bo01", "bo02" and "bo03" are the three current bosses, and spawn after a warning is flashed on screen. Note that two bosses cannot be spawned within a short period of eachother. (and probably not even on the same level, this is largely untested).
  • The third cell is what side of the screen the enemy will enter. Top, Left, or Right (mostly untested).
  • The final cell is the coordinate the enemy spawns at.
    • For Top spawning enemies, this number is the X-coordinate they spawn at (between 0-400 for left-right).
    • For Left and Right spawning enemies, this is the Y coordinate (0-240 for top-bottom).



Left/Right - Increase/Decrease difficulty, Change the level (hold Y to speed-cycle)

A - Select

B - Back (only works on ship select screen)

In game:

D-Pad - Move

Y - Fire Primary

R - Focus Mode (halve movement speed, and uses an alternate weapon)

Start - Return to Menu

Select - Take Screenshot


EUCLIOD 3DS - A Homebrew Bullet Hell (hexzyle)

Eucliod - Stylistic Bullet Hell! | 3DS Homebrew Showcase (TCPixel)

Known issues

Crash on N3DS with Luma 10.2.1.


Release 7

  • Bullets now clear on stage clear.
  • Control configuration and theme does not currently save as the config file is in a read-only location.
  • Sounds have been disabled as a crippling bug in CIA form causes sounds to loop and memory leak, have not identified how to solve this problem.
  • As the CIA is a compiled installation, there is not currently a way to use custom levels with the CIA version.

Release 6.1

  • Re-added a null file that had been accidentally removed, to fix the red bar loading issue.

Release 6

  • Added sound effects
  • Color scheme is now changeable from options menu. (includes high contrast black and white mode).

Release 5

  • Added new enemy, "Kamikaze".
  • Added new enemy, "Asteroid".
  • Enemies now will kill you on contact.
  • Added Level 3, featuring the two new enemies and a new boss, "Odin's Fleet".
  • Bosses now clear bullets before starting the next phase.
  • Corrected a calculation error with the scoring (Difficulty was linearly increasing score instead of multiplicatively).
  • Made some dramatic hitbox corrections for enemy ships.
  • Increased Level 1 and 2 boss health by 140% to counter the hitbox change.
  • Grazing has temporarily been removed as a new, faster, and pixel-accurate player hit detection system has now been implemented. Grazing may be added back in a later update.
  • Fixed a bug that was causing homebrew launched after EUCLIOD to have messed up graphics.
  • FPS counter (hopefully should remain at 60 at all times).
  • Boss health bar.
  • Debug mode (hold X before loading screen displays) includes "slideshow" recording which replaces screenshots, displays a couple debug values on the bottom screen, and ups Level 1's boss's final attack to one hundred and eleven for testing lag.
  • Fixed a bug that was causing multiple level's enemies to load if you chose a level then backed out of the ship select screen before choosing another level.
  • Credits added.
  • Further improvements to overall system stability and other minor adjustments have been made to enhance the user experience.

Release 4

  • Added variation to Level 2 boss's tidal wave attack to eliminate safespots.
  • Added two ship types: "Tiger" and "Cicada".
  • Ship selection screen.
  • The original ship, "Hawk", received a 25% movement speed reduction.
  • Weapons are no longer freely scrollable. Each ship has a Primary weapon and a Focus weapon, which automatically engages when you enter focus mode. You can press Y on the ship selection screen to disable the focus weapon, which causes the Primary weapon to be used for both modes.
  • Corrected a bug that was preventing enemies from despawning and thus the level from being cleared.
  • Increased graze range by 30% and doubled point reward for grazing.
  • Taking screenshots now works.

Release 3

  • Added level 2, including a new enemy (Helix "en04") and a new boss "bo02".
  • 3 New bullet types used by these two enemies: "Sway", "Diagonal", and "Moving Orbitals".
  • Corrected bug that was causing previously loaded level's enemies to spawn (only matters if anyone actually made any levels).
  • Buffed seeker shot damage and tracking.
  • Nerfed missile's hitbox.
  • Exit button works now (big whoop).
  • Tweaked strafers so that they're not so insane on lower difficulties.
  • Basic enemy shots now travel slower but have larger hitboxes.
  • Basic score counter implemented. Kills and graze count towards score.
  • The game will now return to menu once the level is cleared.
  • Shortened enemy despawn time to reduce lag.
  • Buffed boss health.
  • Added "Stage Clear" text. Game will return to menu shortly afterwards.

Release 2

  • Substantial optimization regarding boss bullet spawns, seeker rounds, all player shots in general, and moving enemies.
  • N3DS mode automatically activates for N3DS systems. O3DS mode can still be forced by holding Y upon launch.
  • Combined, these two changes create a DRAMATIC performance boost for the game, so you can look forward to a lot more bullets in the future.
  • The game now returns to menu several seconds after a death. You can still reset early by pressing Start.
  • Custom keybinds menu added. Keybind settings are persistent.
  • Enemies now despawn after 1000 ticks.

External links