Here is a buide about thief critical. Now I share it with you.
This build is for pvp and also good for DPS for dungeons.
All reg skill upgraded since only money is involved
swift atk (max)
hidden force (max)
deadly containment (max)
not sure if CP will cover all skills at max so im trying to save
Art of assassination lv10
art of insight lv10
Hunter certificates will help a lot Luck and crit dmg
with luck+ , Crit dmg+ , CRit rate+ or Str+ bonuses
wepons with luck+ , Crit dmg+ , CRit rate+ or Str+ bonuses too dagger for pvp; dagg or sword for pve
source:Thief Critical explosive build.