Board Thread:Warhammer 40k General Discussion/@comment-25686730-20141212030710/@comment-24944355-20141213050648

You take the librarius out of the equation for the loyalist chapter then add in the demonic force multiplier of the sorcerer & a truly powerful Thousand Son sorcerer can easily match a loyalist chapter, which is what I meant by a top tier sorcerer matching a chapter of ordinary marines.

As for Magnus the reason he was duped so easily by Tzeentch is that he was blinded by his own arrogance & his certainty in being smarter than anyone else. After what happened to his legion at Tzeentch's design a lot of that arrogant certitude got knocked out of him, he is a much more cautious individual now & a much better long term planner. Now it's Tzeentch who is so certain of his own infallibility that he has become vulnerable to Magnus plotting.

As for Perturabo he is probably the most active of the demon primarchs but his legion would rank behind the Death Guard & the Word Bearers when it comes to the damage they do to the empire. And while Alpharius &/or Omegon are the most cunning & dangerous of the fallen primarchs he/they don't appear to be plotting to replace any of the chaos gods but that's because NO ONE has ANY idea what his/their plans actually are!