After seeing it said that a bug with thrown weapons was found and that now maybe shuriken crit expansions might work. Well after some testing I have to say that this one does not. It shows a crit expansion by two in tool toop, but in function...
without improved crit throwing it showed 18-20 crit range
with improved crit throwing it showed 18-20 crit range
with improved crit I was getting crits on 19 and 20s, without improved crit only on 20..... I used various level 28 random gen shurikens from ah and mourning star from ah.
As nice as it would have been with stars being added to the craftable thunderforged... ithe ninja spy shuriken crit expansion cap stone still doenst work.