SaltAddict's MK2 Johnny Cage throws an error in the latest Ikemen nightly build. Apparently the error was caused due to a change in the gethitvar(attr) trigger.
https://github.com/ikemen-engine/Ikemen-GO/wiki/Triggers-(changed)#attr-nightly-build-only

Link for the character: https://mugenguild.com/forum/topics/johnny-cage-mk2-v1-0-199221.msg2562797.html

(I tried to report this error in the original topic, but the post was moved to the trash can for some reason.)