While Doctor Doom is active, each non-Villain character gets -1A and -1D (no matter how many Doctor Doom dice you have fielded)
Page 18 of the AVX rulebook state:
Once gained, bonuses last until the end of the turn
I would like some additional clarification on the interaction of "While active" abilities and the rulebook statement from above. If I have Doctor Doom - Reed Richards' Rival and a level 1 Iceman - Cryokinetic fielded (normal stats of 2A/4D so modified to 1A/3D by Doctor Doom), and Doctor Doom gets knocked out, would Iceman remain 1A/3D until the end of turn, or would he immediately go back to 2A/4D?