I believe the E.M.P. Modification node on Mr Sinister (and possibly elsewhere) is bugged. It appears that when certain buffs expire, Mr Sinister gains an EMP Modification charge. I noticed this with the dexterity buff, as well as Medusa's furies. This means that Mr Sinister is gaining a charge at the time the buff starts, and when the buff expires. I don't see this anywhere in the node description and this is making the node nearly twice as difficult to deal with.
Not trying to push my content here, but this video is the best example of the bug. The medusa fight starts at 2:52 into the video. At 3:20 you can see my furies expire, and Sinister's charges go from 5 to 7 without me gaining another buff. You can also see dexterity giving Sinister a second charge when I use Hyperion, starting at 1:20. Once on activation, and once when I attack, getting rid of the dexterity buff.
https://www.youtube.com/watch?v=J_qRXM-b5yY