MythicMobs just updated from 4.14.1 to 5.0.1(beta) 11 hours ago on SpigotMC, I'm not 24/7 monitoring for any plugin updates. Are you expecting me to update my plugin right away instantly without any testing?
Also, according to MythicMobs changelog (
https://git.mythiccraft.io/mythiccraft/MythicMobs/-/wikis/Changelogs#501-beta-build), they have made "Mythic API being separated out into an independent module (for add-on authors)" and "Major API rewrite", which means that it might take much longer time to reconfigure the dependencies FOR MY IDE in order to start adding new version support, as well as old version compatibility. It is impossible for me to complete these within 11 hours (also I have my own sleep schedule too).
Moreover, as stated in Terms of Use, you are not recommended to give reviews about the difficulty you are facing like bugs, errors, configuration problems, and obviously, this is an error.
No support will be given until MythicMobs releases an updated version of API Information.