Creature Spawn Chance Fix

Creature Spawn Chance Fix

Requirements:

None

Preface

After testing the vanilla behaviour and doing statistical analysis, it does not appear that this fix is actually required. The information on the CS Wiki Leveled Creature page and other sources is incorrect, and the vanilla game correctly calculates each creature spawn independently.

The extra file is also not required, and the 'Chance None' of 128 just seems to enable the 'Calculate from all levels <= player's level' flag, as guessed below.

This mod page will be left up for archival purposes.

Description

This is a comprehensive fix for a known bug relating to creature spawn chances. The game only rolls once for spawn chance when a cell is loaded, meaning that all creature spawn points within a cell are linked to that one roll. In effect, this means that all chanced spawn points within a cell will either spawn a creature or not. In other words, it's all or nothing.

This mod implements a workaround for the above issue. Now all spawn points will roll independently of one another, as intended. The base game and Shivering Isles is covered; no other DLC uses chanced spawns.

An example of the bug and fix is given below, in case my description doesn't make much sense.

• []A cell contains three creatures with a 75% chance of spawning, i.e. a 25% chance of not spawning.

  []In vanilla, you enter the cell: the game rolls once on 1 to 100, and the outcome is 85. All creature spawns are based of this roll, and since 85 is greater than 75, no creatures spawn.

• With this fix, you enter the same cell: the game will 'roll' three times, once for each of the three spawns. The outcomes are 85, 17, and 54, so one creature doesn't spawn, and the other two do.

  How it Works

  This bug and the workaround to fix it have been known for a long time—it is actually included in some of the old overhaul mods like OOO. However, to my knowledge, no-one has ever provided a standalone fix, probably due to the time-consuming and tedious task of manually editing all the chanced creature leveled lists.

  The "Chance None" for all chance-based creature spawns has been set to 0. Instead, the creature leveled lists are weighted using a dummy null spawn, which doesn't produce a creature. For example, a 75%-chance list is weighted in a 3:1 ratio using three entries for the 100%-chance list for the same creature spawn, and one entry for the the dummy spawn. A