big spoilers...
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big big big MAJOR spoilers...
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about the ToB NPC
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so if you don't know who that is, DON'T READ ANY MORE
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Is the ToB NPC's alignment change triggered by an event or a random banter?

Is a banter on a random timer. Some people get it early, some never get it.

The ascension mod fixes this so its a more reasonable time.

It's random, but you have to have made the right choice when you got him. You can't force him to swear the oath.

If you're getting impatient, just spread out the rest of your party so they can't see you or one another, stand next to Sarevok, and whack CTRL+I until he talks to you.

*comes back from the July 4 celebration in Washington DC*

Just wondering about the timing on it, because I never got it in my first game with my first party with the ToB NPC, but I did with the second and wasn't sure what I did to induce it.

Ctrl-I? I take it this is activated as all the cheats (ie. first editing that file) but what does it do?

CTRL+I tries to fire an interparty banter. Lovetalks are actually specialized forms of banter, so it's possible although unlikely one can get an LT instead.