Unarmed lit bombs

Verified against the spelunky.ai port v0.1.10 on 28 October 2026.

A lit Bomb the player throws is armed, which the game checks in two places: a Bomb going through an exit in his hands is let go and left behind, and one near a shop angers its Shopkeeper. Bombs lit by other things look and burn the same but aren't armed, so neither check acts on them.

The player opens a Chest, and out pops a lit bomb. He picks it up and takes the exit with it: instead of being left behind, it goes back into his bag, and his bombs go from 4 to 5 ^[1].

One time in 12, opening a Chest lets out a trap: a Bomb with the lit sprite and a 40-step fuse, but armed, which every item starts without, is never set ^[2]. At a level's exit, the player's step lets go of an armed Bomb and puts any other back in his bombs ^[3]:

else if (holdItem.type == "Bomb")
{
    if (holdItem.armed)
    {
        holdItem.held = false;
    }
    else
    {
        global.bombs += 1;
        with holdItem { instance_destroy(); }
    }

That's what puts an unlit Bomb carried out back in the bag, and the trap bomb, lit but unarmed, goes back in too. Olmec's exit does the same ^[4]. A Bomb near a shop angers its Shopkeeper only if it's armed ^[5].

Only the player's throw, a Monkey and the Sun Room arm a bomb; an explosion setting one off, a Magma Man's touch and the mothership's barrier light it unarmed. The player being stunned or killed arms whatever he drops ^[6]. Of the unarmed ones, only the Chest's burns long enough to carry out: the others go off in 4 to 12 steps ^[7].

Open Chests until one lets out a bomb, pick it up at once and walk through the exit within its 40 steps. The replay of the clip's staged scene pins it: the trap bomb, unarmed, picked up lit and taken through the exit, puts the bombs from 4 to 5, with no explosion ^[8].

The spelunky.ai port reproduces it exactly: it's in docs/quirks.md's list of the 1.1 source's bugs ^[7], and the oracle's fingerprint of the replay pins the bomb count. The Shopkeeper's side is read in the code and not yet in a replay. No option turns it off.