AEKey Legacy is a library mod for Minecraft 1.12.2 that backports the AEKey API from AE2 version 1.20.1. This mod does not add any game content itself and serves only as a prerequisite for the development and use of other mods.

The following are the main adaptations made during this backporting process:

• Adjusted the isTagged method of AEKey to change its parameter from TagKey<?> to String, and modified the overridden methods to be compatible with the Ore Dictionary system.
• Changed the return type of AEKeyType.getTagNames from Stream<TagKey<?>> to Stream<String> to also adapt to the Ore Dictionary system.
• In AEItemKey, the original cachedDamage field was renamed to metadata. Methods to retrieve the metadata and to check if a variant exists based on metadata were added.
• The creation, comparison, and serialization processes for AEItemKey now all support metadata.