Dimension Amplifier & MobScaler

Dimension Amplifier & MobScaler is a Forge game mechanics mod that changes mob attributes on the fly. Instead of relying on time elapsed or distance from the spawn point, which many similar mods use, it adjusts the base and additional values of mob health, armor and damage through dimension and difficulty multipliers. A spider with a base of 16 health and 5 additional health, scaled by a dimension multiplier and a difficulty multiplier, ends up with about 48 health after rounding.

The mod can be restricted with a blacklist of entities, and it exposes configuration options that other mods can use to define custom settings. Its author describes the current build as a testing phase, with essential vanilla attributes planned for later updates and other attributes still under consideration. The code is under the MIT License, and the project is not open source.