ToME: the Tales of Maj'Eyal

I was fighting some randboss forest wight sawbutcher and all of a sudden the screen started blinking black, so i alttabbed and the log file has this:

[LOG] Elowen the forest wight's Shoot hits #fbd578#Rormov#LAST# for #aaaaaa#4 physical#LAST#, #ROYAL_BLUE#(3 antimagic)#LAST#, #ROYAL_BLUE#0 lightning#LAST#, #1133F3#(4 antimagic)#LAST#, #1133F3#0 cold#LAST# (4 total damage).
[LOG] #UID:6719:0##fbd578#Rormov#LAST# hits Elowen the forest wight for #aaaaaa#37 physical#LAST#, #aaaaaa#6 physical#LAST#, #PURPLE#0 arcane#LAST#, #PURPLE#68 arcane#LAST#, #PURPLE#0 arcane#LAST#, #PURPLE#0 arcane#LAST# (111 total damage).
[LOG] Mana Clash hits Elowen the forest wight for #PURPLE#0 arcane#LAST#, #PURPLE#0 arcane#LAST#, #PURPLE#0 arcane#LAST#, #PURPLE#0 arcane#LAST#, #PURPLE#0 arcane#LAST#, #PURPLE#0 arcane#LAST# (0 total damage).
Deleting shader 102 (is clone 1)
Lua Error: /mod/class/uiset/ClassicPlayerDisplay.lua:271: bad argument #1 to 'format' (no value)
At [C]:-1
At [C]:-1 format
At /mod/class/uiset/ClassicPlayerDisplay.lua:271 display
At /mod/class/uiset/ClassicPlayerDisplay.lua:463 toScreen
At /mod/class/uiset/Classic.lua:326 display
At /mod/class/Game.lua:1732
Lua Error: /mod/class/uiset/ClassicPlayerDisplay.lua:271: bad argument #1 to 'format' (no value)
At [C]:-1
At [C]:-1 format
At /mod/class/uiset/ClassicPlayerDisplay.lua:271 display
At /mod/class/uiset/ClassicPlayerDisplay.lua:463 toScreen
At /mod/class/uiset/Classic.lua:326 display
At /mod/class/Game.lua:1732
Lua Error: /mod/class/uiset/ClassicPlayerDisplay.lua:271: bad argument #1 to 'format' (no value)
At [C]:-1
At [C]:-1 format
At /mod/class/uiset/ClassicPlayerDisplay.lua:271 display
At /mod/class/uiset/ClassicPlayerDisplay.lua:463 toScreen
At /mod/class/uiset/Classic.lua:326 display
At /mod/class/Game.lua:1732
[MIND CRIT %] 22.7
[LOG] Rormov is invigorated by the attack!
[LOG] #00ff00##UID:451:0#Talent Shield Pummel is ready to use.
[LOG] #00ff00##UID:453:0#Talent Shield Slam is ready to use.
[LOG] #UID:6719:0##fbd578#Rormov#LAST# hits Elowen the forest wight for #PURPLE#3 arcane#LAST# damage.
[LOG] Mana Clash hits Elowen the forest wight for #PURPLE#0 arcane#LAST# damage.
[LOG] Bleeding from Elowen the forest wight hits #fbd578#Rormov#LAST# for #aaaaaa#1 physical#LAST# damage.
[LOG] Decrepitude Disease from Elowen the forest wight hits #fbd578#Rormov#LAST# for #DARK_GREEN#(15 antimagic)#LAST#, #DARK_GREEN#0 blight#LAST# (0 total damage).
[LOG] Elowen the forest wight shoots!
[ARCHERY ACQUIRE TARGETS WITH] ranger's dwarven-steel steamgun of lightning elemental pouch of dwarven-steel shots nil nil
[SHOOT] speed 1 => 1000
[ARCHERY SHOOT] Elowen the forest wight 21910 using weapon: ranger's dwarven-steel steamgun of lightning ammo: elemental pouch of dwarven-steel shots offweapon: nil pf_weapon: nil
[ARCHERY SHOOT dofire] Shooting weapon: ranger's dwarven-steel steamgun of lightning to: 34 28
Adding entity 23709 after 21910
[LOG]
Lua Error: /mod/class/uiset/ClassicPlayerDisplay.lua:271: bad argument #1 to 'format' (no value)
At [C]:-1
At [C]:-1 format
At /mod/class/uiset/ClassicPlayerDisplay.lua:271 display
At /mod/class/uiset/ClassicPlayerDisplay.lua:463 toScreen
At /mod/class/uiset/Classic.lua:326 display
At /mod/class/Game.lua:1732
Lua Error: /mod/class/uiset/ClassicPlayerDisplay.lua:271: bad argument #1 to 'format' (no value)
At [C]:-1
At [C]:-1 format
At /mod/class/uiset/ClassicPlayerDisplay.lua:271 display
At /mod/class/uiset/ClassicPlayerDisplay.lua:463 toScreen
At /mod/class/uiset/Classic.lua:326 display
At /mod/class/Game.lua:1732
Lua Error: /mod/class/uiset/ClassicPlayerDisplay.lua:271: bad argument #1 to 'format' (no value)
At [C]:-1
At [C]:-1 format
At /mod/class/uiset/ClassicPlayerDisplay.lua:271 display
At /mod/class/uiset/ClassicPlayerDisplay.lua:463 toScreen
At /mod/class/uiset/Classic.lua:326 display
At /mod/class/Game.lua:1732

and that LUA error is spammed over and over and over and over and over and over and over again