Here are three articles from Springhole.net that should help you and that I have referenced when writing a manipulative character.

Writing Liars and Manipulators.

Writing Brainwashing.

Writing Abusers and Abuse Situations.

And here is the TV Tropes page on More Than Mind Control that should give some ideas as well.

oooo the eggpire. I think it has some really interesting potential and it feels like it's building up to something big. I’ve enjoyed seeing people be slowly corrupted and now that the main storyline is on a break its good that it has some time to shine. I know Bad and Ant’s plan is to let the egg spread to everywhere on the server to cause total chaos and I'm excited to see how that'll play out - and how certain characters will react to it (like Techno)

I have to be honest in saying that a lot of the stuff I know about the eggpire has been second hand, mainly because the timezones for watching the streams are weird and I was a bit overwhelmed trying to keep up with the main storyline and the eggpire.

Sounds cool!  It seems like you could have a lot of fun with it in your story.  Stealthy poisons are always a great way for conflict to happen!