Actions with merms crash server

I'm not sure what the action is to be honest but it seems to be befriending them? See log excerpt below.

[06:11:27]: [string "scripts/entityscript.lua"]:1306: assertion failed!
LUA ERROR stack traceback:
=[C]:-1 in (global) assert (C) <-1--1>
scripts/entityscript.lua:1306 in (method) GetDistanceSqToInst (Lua) <1305-1310>
   self (valid:false) =
      GUID = 543716
      DoLunarMutation = function - scripts/prefabs/merm.lua:724
      inlimbo = false
      ShouldWaitForHelp = function - scripts/prefabs/merm.lua:1106
      brain = --brain--
sleep time: 0.22
Priority - RUNNING <RUNNING> (execute 1, eval in 0.22)>0.22
   >Parallel - RUNNING <RUNNING> ()>0.22
   >   >pause for jump - READY <SUCCESS> ()>0.00
   >   >Priority - RUNNING <RUNNING> (execute 15, eval in 0.22)>0.22
   >   >   >Parallel - FAILED <FAILED> ()>0.00
   >   >   >   >PanicTrigger - FAILED <FAILED> ()>0.00
   >   >   >   >Panic - READY <READY> ()>0.00
   >   >   >ChattyNode - FAILED <FAILED> ()>0.00
   >   >   >   >FaceEntity - FAILED <FAILED> ()>0.00
   >   >   >collect armor - FAILED <FAILED> ()>0.00
   >   >   >Sequence - FAILED <FAILED> ()>0.00
   >   >   >   >needs armor - FAILED <FAILED> ()>0.00
   >   >   >   >Priority - READY <READY> ()>0.00
   >   >   >   >   >Leash - READY <READY> ()>0.00
   >   >   >   >   >collect armor - READY <READY> ()>0.00
   >   >   >Parallel - FAILED <FAILED> ()>0.00
   >   >   >   >WaitingForHelp - FAILED <FAILED> ()>0.00
   >   >   >   >Priority - READY <READY> ()>0.00
   >   >   >   >   >Follow - READY <READY> ()>0.00
   >   >   >   [**truncated**]
      dohiremerms = function - scripts/prefabs/merm.lua:287
      sounds = table: 61DFF720
      AnimState = AnimState (96CFCB58)
      reverting = true
      wantstoteleport = true
      Network = Network (96CFD3F8)
      physicsradiusoverride = 0.5
      DoDisapproval = function - scripts/prefabs/merm.lua:406
      state = run_stop
      sg = sg="merm", state="idle", time=2.20, tags = "idle,canrotate,"
      spawntime = 64166.170013193
      ismerm = true
      Physics = Physics (96CFD558)
      name = Gurt
      return_to_king = false
      scrapbook_damage = table: 340B0940
      TestForLunarMutation = function - scripts/prefabs/merm.lua:796
      _last_hitreact_time = 64221.236682732
      actionreplica = table: 7E04E8D8
      scrapbook_deps = table: 340B0260
      actioncomponents = table: 7E04E478
      DoThorns = function - scripts/prefabs/merm.lua:716
      lower_components_shadow = table: 7E04E428
      updateeyebuild = function - scripts/prefabs/merm.lua:869
      Transform = Transform (96CFB838)
      entity = Entity (77B684F0)
      CanTripleAttack = function - scripts/prefabs/merm.lua:1119
      prefab = mermguard_lunar
      scrapbook_hide = table: 61E03410
      OnSave = function - scripts/prefabs/merm.lua:617
      TestForShadowDeath = function - scripts/prefabs/merm.lua:656
      persists = false
      DynamicShadow = DynamicShadow (96CFD158)
      brainfn = table: 61E02628
      planarbuffed = net_bool (6049C478)
      MermDamageCalculator = function - scripts/prefabs/merm.lua:100
      modactioncomponents = table: 340B2330
      DoCheer = function - scripts/prefabs/merm.lua:397
      originalowner_gamedate = N/A
      replica = table: 7E04E590
      OnLoad = function - scripts/prefabs/merm.lua:650
      components = table: 7E04E248
      SoundEmitter = SoundEmitter (96CFCB78)
   inst = 129372 - mermwatchtower (valid:true)
scripts/prefabs/merm.lua:206 in (upvalue) resolve_on_attacked (Lua) <193-213>
   inst = 543716 - mermguard_lunar (valid:false)
   attacker = 538135 - wurt (valid:true)
   isguard = true
   share_target_dist = 60
   max_target_shares = 8
   home = 129372 - mermwatchtower (valid:true)
scripts/prefabs/merm.lua:225 in (local) fn (Lua) <223-227>
   inst = 543716 - mermguard_lunar (valid:false)
   attacker = 538135 - wurt (valid:true)
scripts/entityscript.lua:1215 in (method) PushEvent (Lua) <1202-1229>
   self (valid:false) =
      GUID = 543716
      DoLunarMutation = function - scripts/prefabs/merm.lua:724
      inlimbo = false
      ShouldWaitForHelp = function - scripts/prefabs/merm.lua:1106
      brain = --brain--
sleep time: 0.22
Priority -
[06:11:27]: [string "scripts/entityscript.lua"]:1306: assertion failed!
LUA ERROR stack traceback:
    =[C]:-1 in (global) assert (C) <-1--1>
    scripts/entityscript.lua:1306 in (method) GetDistanceSqToInst (Lua) <1305-1310>
    scripts/prefabs/merm.lua:206 in (upvalue) resolve_on_attacked (Lua) <193-213>
    scripts/prefabs/merm.lua:225 in (local) fn (Lua) <223-227>
    scripts/entityscript.lua:1215 in (method) PushEvent (Lua) <1202-1229>
    scripts/prefabs/mermking_gear_buffs.lua:70 in (field) ondodgefn (Lua) <70-70>
    scripts/components/attackdodger.lua:39 in (method) Dodge (Lua) <37-47>
    scripts/components/combat.lua:549 in (method) GetAttacked (Lua) <530-651>
    scripts/components/combat.lua:1153 in (method) DoAttack (Lua) <1066-1177>
    scripts/components/projectile.lua:220 in (method) Hit (Lua) <200-227>
    scripts/components/projectile.lua:294 in (upvalue) DoUpdate (Lua) <266-333>
    scripts/components/projectile.lua:361 in (method) OnUpdate (Lua) <335-362>
    scripts/update.lua:262 in () ? (Lua) <224-298>

Full log included.