Yes, this is the demoralize effect, and it does come from your assassin strike. It's something that all the sets do, and it was part of the stalker revamp a few issues back. Basically the idea is that suddenly a stalker jumps out of nowhere and eviscerates some poor sap, and all the baddies recoil in fear. It's very thematic and (imo) quite satisfying. 
@MuonNeutrino
Student, Gamer, Altaholic, and future Astronomer.
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The way it works is you have to AS the target and the target has to live or die and rez for the effect to work. Then the fear effect kicks in but its a chance to do this. Also it gives a debuff that is non-resistable which is also nice. Stacks very nicely on a stalker heavy team too.
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Hi all,
I just rolled my dark/ninja stalk and as I got up to lvl 8, It seems one (or more) of my powers give an inconsistent fear effect to the PvE opponents. I was not aware of this component, and I think Assasin's Eclipse is probably the power that is doing this (the big bad azzz skull is whats giving me that idea). I looked in both City of Data and power info in game but do not see the fear effect listed. Is this the demoralize thing (and if so all sets are granted this effect?)
Thanks in advance!
-Sin6
I am PL in RL.
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