Xeno Slasher is ground targeted (this means, if the AI tries to use it on a zenorc, it will cast it on the ground where it's standing, and it could move by the time the cast ends.
On AzzyAI the settings specific to this skill are:
UseEiraXenoSlasher
EiraXenoSlasherLevel
As an AoE skill, it's behavior is controlled by the usual options:
AutoMobCount - number of monsters above which to use AoE. This respects TACT_WEIGHT, so you can have it count some monsters are more or fewer than 1.
AutoMobMode - Either 0/disabled (no AoE skill use), 1/Aggressive (count only monsters attacking you or homun), 2/All (count all monsters that will be caught in the AoE)
And these true/false ones:
AoEReserveSP - Reserve enough SP to use the AoE (ie, don't use other skills if they would leave it without enough SP for the AoE - this prevents sp-limited homuns from getting stuck using lower-sp-cost single target attack and never getting enough SP for AoE)
AoEFixedLevel - When targeting AoE skills, ignore the skill level tactic, and force it to use the level specified by EiraXenoSlasherLevel. Useful if you specify lower levels to conserve SP when using single target skills.
AoEMaximizeTargets - Adjust the point on the ground to target skill on in order to maximize targets hit (assuming they don't move).
I will add the documentation for AutoMobMode in the next release. Somehow that seemed to get lost from the docs.
I think it's one of the ones that I lost docs for when I lost the thumb drive containing the .doc file that I generate the pdf from, and wound up having to rewrite all the new options, (since going from pdf back to doc introduced so many formatting problems it was easier to just rewrite what I'd lost).