The red Lamp gives no light

On a dark level, a Lamp carried or lying on the ground lights the cave around it, and the player's own light widens as he nears it. The Kissing Parlor's lamp is red, and while it hangs it lights the shop like any other. Once its block is broken and it falls, though, the red Lamp lights nothing: in the dark, carrying it is the same as carrying nothing, but for a red tint.

On a dark level, the player throws a lit bomb up under the Kissing Parlor's ceiling, and the red lamp falls. He picks it up and carries it out of the shop into the dark: it casts no light of its own, the dark closes in round him as if his hands were empty, and only the red tint shows ^[1].

The red hanging lamp, oLampRed, is a kind of the plain one, oLamp, in the game's objects. The red Lamp it falls as, oLampRedItem, is an item like any other, not a kind of the plain Lamp, oLampItem ^[2]. On a dark level the screen draws a circle of light round every hanging lamp, which takes in the red one, and round every fallen Lamp, which names the plain one only:

            with oLamp
            {
                draw_circle((x+8)-view_xview[0], (y+8)-view_yview[0], 96, false);
            }
            with oLampItem
            {
                draw_circle(x-view_xview[0], (y-4)-view_yview[0], 96, false);
            }

The player's step, which finds the nearest light to set how dark it is round him, looks for the same two ^{[3] [4]}. The red Lamp appears in the lighting code only where it tints the lights red while the player is within 96 pixels of it ^{[5] [6]}.

Find a Kissing Parlor on a dark level: the Mines' levels 2 to 4, the Jungle or the Temple, or any level defiling a third altar, or a later one, makes dark, the Ice Caves' too. Its lamp hangs from the shop's ceiling, out of reach of a bomb on the floor, and a lit bomb near the Shopkeeper in his shop angers him, so deal with him first, then throw a lit bomb up under the lamp as its fuse runs out. Pick the red Lamp up and walk into the dark. The replay of the clip does so on a dark level 2: carrying the red Lamp, the nearest light the player has is never closer than 20 pixels, and the darkness reaches its deepest ^[7]. Another replay brings a dark level's plain lamp down and carries it, and the darkness is gone while he does ^[8].

The spelunky.ai port reproduces it exactly: it's in docs/quirks.md's list of the 1.1 source's bugs ^[6], and the oracle's fingerprints of the two replays pin the light round the player with each Lamp. No option turns it off.