Right now, Dark Sight seems to be delayed ever so slightly upon activation. By this I mean that it takes ~0.5-1 seconds for Dark Sight to take effect once you've used the skill. Part of this is because of your own latency, yes, but this is limited and in no way up to 1 second. As far as my knowledge goes, this was not the case in gMS; I have checked if it has been changed between v62 and v83, and have not found a change, and on all v83 servers I have played, Dark Sight was instant. I also recall Dark Sight being instant on my Night Lord on gMS. Now, this might seem insignificant and a trivial bug; however, this is stopping Shadowers from pinning Bigfoot correctly and efficiently, which is (for lack of a better word) a pain in the ass. For more questions, just hit me up in-game or here, I'll see what I can do to help further to get this fixed ASAP. Edit: This is the same for the Dark Sight deactivation, which is the main cause of trouble for Shadowers when it comes to pinning Bigfoot.
I've noticed this happening too. There's a good 1 second delay after hitting the key and hearing the sound, and in that second you're still able to be hit by anything that touches you.