Warpstone Flux Rating: ⭐️⭐️⭐️⭐️
4/5 stars. The rules are strong.
Imperial Fists Armoury.
There are a number of unique and semi-unique entries in the Imperial Fists armoury.
Vigil Storm Shield.
This is the 3++ invulnerable saving throw that is otherwise largely absent from Horus Heresy / 30k. The points cost with purchasing it is very reasonable, but will add up quickly if the goal is a full squad of thunder hammer and vigil storm shield terminators. Worth it for a true death star unit, and similarly for an important character.
The access to deep striking is a very strong rule and competes superbly well. The points cost again adds up fast here so take this only for a dedicated unit. Take a different rite of war to give everyone relevant deep strike if that's the build you're after though.
Solarite Power Gauntlet.
A power fist or thunder hammer upgrade that appeared in the first edition. Here it is a nice upgrade and worth it for characters.
Iliastus Assault Cannon.
Exchanging heavy flamers or predator mounts for this assault 4 weapon is very tempting. When combined with some of the Imperial Fists other rules, this can be very powerful in second edition.
We will review the Castellan unit distinctly.
Difference to First Edition.
Very Neutral. There are some changes, but overall the rules are broadly comparable.