Gun Modules

Gun modules are containers that change which weapon the player's gunboots fire. They are found in safe zones. During the boss fight, heart-type modules spawn inside the arena's sections (the module type is forced to heart in area 5, at most one per section). Each module is stamped with a letter showing which weapon it holds, and picking one up always swaps your current weapon for the new one; a module never contains the weapon you are already carrying, unless it is re-rolled with Reverse Engineering.

Weapons

Machinegun

Burst

Laser

Noppy

Puncher

Shotgun

Triple

Module types

Every module also comes in one of two container types, granting a small bonus on pickup:

Battery: +2 charges

Heart: +1 hp

Trivia

• Shooting a gun module while the Reverse Engineering upgrade is active re-rolls the weapon inside. A re-rolled module may contain the weapon you already have, which is the only way that can happen.

Implementation

Every weapon is a row in one data table. No weapon has its own object or script.

The weapon table

bStatInitLevel1.gml builds parallel arrays named global.bStat*[id][level]. A counter (gunnum) starts at 0 and is incremented between blocks, so each block of assignments defines one weapon: Machinegun is id 0, Shotgun 1, Laser 2, Triple 3, Puncher 4, Burst 5, Noppy 6. The file ends with global.bulletMaxNum = gunnum;, which records the highest valid id. Every stat has two entries per weapon: [id][0] holds the normal values and [id][1] the Gem High values.

A new weapon is a new block in this file (with its own gunnum += 1) placed before the bulletMaxNum line. Gun modules roll irandom(global.bulletMaxNum), so a new id enters the pickup pool with no other change.

Fields

Field	Verified behaviour
bStatName	Text shown on pickup. bStatJp.gml overwrites ids 0 to 6 with Japanese names when the language is Japanese.
bStatGunSprite	Frame index into the sprModText sprite: the letter glyph drawn on the module (frame 12 is M, 18 is S, 11 is L, 19 is T, 15 is P, 1 is B, 13 is N).
bStatObject	The projectile object created per shot. Ids 0, 1, 3, 4, 5, 6 use bulletRanged; the Laser uses bulletLaser.
bStatBulletSprite, bStatSound, bStatMuzzle	Sprite, sound and muzzle-effect assets, per level.
bStatConRate	Charge consumed per shot.
bStatRof	Shot cooldown: the firing script sets its cooldown alarm to abs(Rof) frames, and a negative value additionally marks the shot non-automatic (the button must be released before the next shot).
bStatRecoil	Applied to the player's vertical speed; negative values push upward.
bStatScreenShake, bStatScreenShakeDur	Screen shake strength and duration per shot.
bStatBurst, bStatBurstRate, bStatBurstAmount	With Burst set to 1, one press fires BurstAmount rounds spaced BurstRate frames apart. The Shotgun uses rate 0 (all pellets at once); Burst uses rate 5.
bStatDamage, bStatSpeed, bStatAccuracy, bStatPierce	Damage per projectile, projectile speed (0 for the instant laser beam), random angular spread, and whether the projectile passes through enemies.
bStatSpType, bStatSp1, bStatSp2	Shot pattern. Type 0 fires one projectile. Type 1 adds a pair per step of Sp1, angled ±(Sp2 × step) degrees (Triple: Sp1 1, Sp2 14, giving 3 bullets in a fan). Type 2 adds a pair per step, offset ±(Sp2 × step) pixels horizontally with the same direction (Puncher: Sp1 1, Sp2 5, giving 3 parallel bullets).
bStatAimAngleLimit	Maximum aim tilt in degrees toward the movement direction (25 for Noppy, 0 for the rest, with AimAngleAccl/Dccl controlling the tilt rate).
bStatDelayKill, bStatWave, bStatExplode, bStatRangeRandom, bStatRangeTimer, bStatSp3	Present in the table and copied like the others; the shipped weapons vary them little.

How the table is used

bStatUpdate(id, level) copies one weapon's row into live global.pBul* variables. It runs when a module is picked up (gun_module's player collision sets global.pGunType and calls it) and when the gem streak crosses the Gem High threshold in either direction (scrControlBeginstepCheck.gml switches the level between 0 and 1). bStatInitialize.gml calls it with id 0 at the start of a run, which is why the Machinegun is the starting weapon.

The firing script (scrPlayerShootN.gml) reads only the pBul* variables: it emits pBulObject through the pattern logic in scrPlayerEmitBullet.gml, subtracts pBulConRate from the charge, and sets the cooldown from pBulRof.