Changelog:

• Minecraft 1.21.4 support
• don't allow structures condition to be used on minecraft versions older than 1.20.4
• update various code to not utilize methods deprecated since 1.21.3
• fix issues with 3rd party plugins ignoring rules in certain situations
• the setting mob-process-delay will properly delay all mob processing instead of some
• remove legacy code around 3rd party plugin usage
• using invalid keys in rules.yml will now show an error and which rule it is in
• rules transforming-mobs-inherit-level and riding-passengers-match-vehicle-level have been removed from rules.yml since they don't do anything
• various event listener have configurable priority in settings.yml
• prevent duplicate custom drops and commands when a custom mob group is used
• pass player context if applicable to external PAPI calls when used in multiplier formulas
• new option in settings.yml ignore-mobs-with-no-player-context
• new debug type: PLAYER_CONTEXT
• very small potential performance improvements
• when debug is enabled, mob that haven't constructed a level yet show as no lvl instead of lvl 0
• the debug timer will no longer adds extra time
• updated to Kotlin 2.1
• gradle version to 8.11.1
• other build config changes
• item-nbt-api-plugin version to 2.14.0
• have PVM output-cap apply to min-range assignment in addition to max-range
• new rule (settings): invalid-placeholder-replacement. when used if a PAPI placeholder returns an empty string then this value is substituted
• fix issue on Folia servers when player count is over 10

Thanks from the ArcanePlugins team:
PenalBuffalo | LevelledMobs4 Developer
lokka30 | Original Author of LevelledMobs
OathKeeper | Support and R&D