I made a Dying Light-like climbing

[manic zealot]

I'm assuming you're using animation rigging for the IK right?

Unity is pretty strict with it's humanoid rigs which sounds like the issue you're running into, but you should be able to just make a generic rig avatar from the model you have and then using the two bone IK constraint to make this work

[hollow raft]

hmm, alright. thanks for help coniix