Megamouth

Verified against the spelunky.ai port v0.1.10 on 27 October 2026.

The Megamouth lives only in the lake at the bottom of a flooded level of the Jungle, one to a level. Four blocks long, it patrols the lake bed and leaves a player on dry land alone, but as soon as he's swimming it charges straight at him. It has 40 hit points, and when it dies, four Crates burst out of it.

A Megamouth swims back and forth along the bottom of its lake at 2 pixels per step (60 per second), sinking 1 pixel a step until it's just above the ground ^[5]. Where the water ends or a wall is in its way, it turns around, if there's room behind it: a turning animation, then a pause of 40 steps (1.33 seconds) ^{[6] [7]}.

As soon as the player is swimming, it attacks, however far away he is in the water ^[8]. It heads for him at 3 pixels per step (90 per second), aiming from its head at him every step, and moves only while the water ahead is clear ^[9]. When he gets behind it, it stops to turn around, with the same animation and pause, before it comes at him again ^[10]. When he leaves the water, it goes back to patrolling ^[11]. The clip shows a Megamouth patrolling the lake bed, charging the moment the player drops into the water, biting him, and turning around as he sinks behind it.

It lets off a bubble every 41 steps ^[12]. It acts while it's within 48 pixels of the screen, farther out than most monsters ^[13].

Out of the water. A Megamouth whose head is out of water loses 1 hit point every step, so its 40 last at most 40 steps (1.33 seconds) ^[14]. The last clip on this page shows it: a Bomb breaks the lake bed, the water drains away, and the stranded Megamouth dies ^[15].

When the player touches a Megamouth without stomping it, he loses 1 heart, is knocked away from it, and blinks, invincible, for 30 steps (1 second) ^[16]. This is the touch code most monsters share. Its body counts as well as its head: it's 64 pixels long and 32 high, and the game moves its collision box to match the way it faces ^[17].

A Megamouth has 40 hit points. The Whip and the Machete hurt it through the code most monsters share, and an explosion through its own, and both take their damage on every step they touch it, with no pause between hits, so one swing of the Whip can take several hit points ^{[18] [19]}. The clip shows the player whipping a charging Megamouth from the water: one swing takes 1 hit point, the next seven, the third three ^[20].

Its own step event replaces the one most monsters share, which is where Spikes, Lava and Spear Traps hurt them, so none of those harm a Megamouth ^[25].

As it's hurt, its body looks more and more bitten: the game draws one of three bodies behind its head, by whether it has 20 hit points or more, 10 or more, or fewer ^[26].

When it dies, it bursts in a spray of blood, leaving four bones, and four Crates fly out of it ^[27]. The clip shows one stranded by a drained lake dying and leaving its Crates. Megamouths killed count toward the player's kills, and the screen between levels draws a Megamouth icon for each ^{[28] [29]}.

Level generation makes a Megamouth only on flooded levels. Each level of the Jungle, levels 5–8, has a 1 in 10 chance of being flooded, unless the player is on his way to the Black Market ^{[30] [31]}. A flooded level opens with "I CAN HEAR RUSHING WATER...", and its two bottom rows of rooms are a lake ^{[32] [33]}. One of the four rooms along the lake's bottom, never the one in the exit room's column, is the Megamouth's, a room of water with one Megamouth in it ^{[34] [35] [36]}.

Custom levels can have them, as the level editor's tile {, a Megamouth in a block of water four tiles wide and two high ^[37].

• A Megamouth only attacks a swimming player, so its lake can be crossed above the water without it giving chase.
• It turns slowly: a player who gets behind it has its turning animation and a 40-step pause to get away.
• One swing of the Whip can take several of its hit points, as can a Machete's.
• A Megamouth out of the water dies within 40 steps, so a Bomb that breaks the lake bed and drains the lake kills it.

• Its object is named oJaws, its sprites sJaws..., and its code calls it "Mega Mouth", two words, while the game's tables name it MEGAMOUTH ^{[38] [39]}.
• That spelling means its kills of the player are never counted. The touch code that tallies deaths by monster checks for "Megamouth", which no monster's name matches, so the deaths-by-enemy table the game writes to stats.txt always shows ??? and 0 in the Megamouth's row ^{[40] [41]}.