Just summoned T4 Grigoire for the first time as an 82 Rogue with a 91 Druid in my party, and all of his red lightning spell effects stopped being visible during the 2nd half of the fight. No red lightning balls flying out from his melee strikes, no walls between the pylons, and no floor tiles lighting up. We were constantly taking damage from the unseen lightning and bouncing off of walls between pylons that we could not see. The other party member was affected as well. Made for a tough fight!
Still happens, after he gets to about 5 mins of the fight things start slowly dissappearing
Still happens in this current season and last on both mine and my wife’s PCs