This plugin seems to have stopped working unfortunately.
Code:
L 07/20/2020 - 01:07:43: [HAMSANDWICH] Failed to retrieve vtable for "player", hook for "hook_TakeConcussionBlast" not active.
L 07/20/2020 - 01:07:43: [AMXX] Displaying debug trace (plugin "concblastblock.amxx")
L 07/20/2020 - 01:07:43: [AMXX] Run time error 10: native error (native "RegisterHam")
L 07/20/2020 - 01:07:43: [AMXX] [0] 19690.attach::plugin_init (line 41)