Moppu/AncientCaveDerandomizer

Cite as: Moppu/AncientCaveDerandomizer
Original: https://github.com/Moppu/AncientCaveDerandomizer
Pinned: Moppu/AncientCaveDerandomizer @ defbe853eb55f63e4663ed30d388fb5822661b61
Accessed: 2026-11-08
Licence: GPL-3.0
Credit: Moppleton ("Moppleton", umokumok@gmail.com). The ac_subr.txt header says it is "documented by Moppleton" and "maybe 60-70% complete".
Notes: A fixed-seed patch tool for the Ancient Cave. `ac_subr.txt` is a partial disassembly and commentary of the vanilla generator ($83:9E31 and $83:9013), with RAM addresses and the RNG loop; `AncientCaveDerandomizer/help/distribution.html` gives the chest categories and the item/blue/consumable threshold tables; EnemyRandomizer.cs names the 0xA595C enemy-by-floor table. The README says the tool is old (circa 2016) and not everything may work.

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No Ancient Cave floor has a seed of its own. The builder draws on the random generator the rest of the game uses, after first spending between 1 and 32 of its numbers, one more than the frame counter's low five bits. That generator is a table of 55 bytes, stirred by XOR each time its numbers run out; it is seeded at power-on and again from a byte kept in the save whenever a save is loaded.	`AncientCaveDerandomizer/help/derandomization.html L6`	Code
Weapon and armour chests deepen with the floor: the builder lists, for each floor, every item marked as found in the field and not marked as excluded whose price is under (floor + 1) × 1,000 gold, or any price from floor 60 on, in item order; items of type 1 go on the weapon list and the rest on the armour list.	`AncientCaveDerandomizer/help/distribution.html L16–22`	Code