I'd almost like him if his armor were invulnerable, or if it were a 2+ save, or if there was check to break magic weapons based on them wounding him before attempting the save, and not after based on him making it. As it is, there aren't many magic weapons worth breaking that won't ignore his 4+ save anyway. In our book I like him better, because at least there he's only a hero and not a lord (not that that matters within the confines of the Nagash campaign rules). He also makes more sense as a bodyguard for Kemmler, as there are a number of characters that Krell could beat on that could legitimately threaten Kemmler. Not so Nagash, especially when Nagash, unlike Kemmler, won't be part of the same unit.
So his bodyguard rule is less useful than before, and I don't see the despair rule and plus one attack making up that difference, let alone the extra cost or shift to lord.
It's a shame, really. Krell's about the only finecast model that I have and like (there are a couple bubbles, sure, but they blend into the worn and beaten texture of his armor).
And I'm still bitter that the Undead Legions list cannot field Kemmler. Even if he wasn't made a mortarch (and he should have been, imo), they could have at least made the VC version available like with the one Tomb Kings character.
And honestly, if they're still following the 'he thinks he works for the chaos gods' bit after Nagash's return? With the fluff that every necromancer in the world can feel Nagash's presence battering at their minds? The 'Kemmler is deluded' fluff worked before, but it doesn't work any longer, and should have been changed to give him a place in this campaign. It is frustrating that the mortarchs include three vampires (none of them necrarchs, the only bloodline to stay loyal to nagash through the ages, but that's a separate gripe), a lich priest, and a wight, but no necromancers at all.
I can only hope their numbers will be expanded in future end times campaign books (much as the Nagash book includes rules for Krom and whatsisname, baby sigmar, you know the one)
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To keep this post from being purely negative, because on balance I'm still very excited about the campaign overall, apparently in the 'Nagash Returns' novel Mannfred is re-retconned to have him lying to Arkhan, pretending to help restore Nagash while secretly planning to betray Arkhan, leave Nagash unsummoned, and make off with the great necromancer's artefacts, which IMO is a decent authorial save in reconciling Mannfred's previous motivations and behaviors with his actions since the start of 8th edition.