(16:25:06) | [Oxide] 18:25 [Error] Failed to call hook 'OnEntityTakeDamage' on plugin 'Freeze v2.2.0' (NullReferenceException: Object reference not set to an instance of an object)
  at Oxide.Plugins.Freeze.OnEntityTakeDamage (BaseCombatEntity entity, HitInfo info) [0x00013] in <447b79be745b418ba5f79bc03a829f1d>:0 
  at Oxide.Plugins.Freeze.DirectCallHook (System.String name, System.Object& ret, System.Object[] args) [0x0043d] in <447b79be745b418ba5f79bc03a829f1d>:0 
  at Oxide.Plugins.CSharpPlugin.InvokeMethod (Oxide.Core.Plugins.HookMethod method, System.Object[] args) [0x00079] in <9affce1cd15c4ec183941adef8db1722>:0 
  at Oxide.Core.Plugins.CSPlugin.OnCallHook (System.String name, System.Object[] args) [0x000d8] in <4452f821def6406d834e4149849fe7ea>:0 
  at Oxide.Core.Plugins.Plugin.CallHook (System.String hook, System.Object[] args) [0x00060] in <4452f821def6406d834e4149849fe7ea>:0

Should be fixed in the latest version.

Thanks

Still seeing this in 2.2.1:

(18:39:31) | [Oxide] 18:39 [Error] Failed to call hook 'OnEntityTakeDamage' on plugin 'Freeze v2.2.1' (NullReferenceException: Object reference not set to an instance of an object)

at Oxide.Plugins.Freeze.OnEntityTakeDamage (BaseCombatEntity entity, HitInfo info) [0x00013] in <19cef70c27f84c3dbdbe1f46d7f2030f>:0

at Oxide.Plugins.Freeze.DirectCallHook (System.String name, System.Object& ret, System.Object[] args) [0x00435] in <19cef70c27f84c3dbdbe1f46d7f2030f>:0

at Oxide.Plugins.CSharpPlugin.InvokeMethod (Oxide.Core.Plugins.HookMethod method, System.Object[] args) [0x00079] in <9affce1cd15c4ec183941adef8db1722>:0

at Oxide.Core.Plugins.CSPlugin.OnCallHook (System.String name, System.Object[] args) [0x000d8] in <4452f821def6406d834e4149849fe7ea>:0

at Oxide.Core.Plugins.Plugin.CallHook (System.String hook, System.Object[] args) [0x00060] in <4452f821def6406d834e4149849fe7ea>:0

Not sure what would still be null here, but I temporarily disabled this functionality (just used for the freeze effect handling).