Really there are only a few options for the Character Stratagem. The most obvious one is taking 3 ven dreads and giving them long ranged weapons (double twin-autocannons, twin las and missile launcher) and make them all characters at the back of your army so they can't be touched. Leave a squad of pain in the rearguard marines defending them as the last line and let the dreads do their thing without need for a captain (since all their weapons are heavy, re-roll 1s and their BS2+ basically makes it full re-roll), more easily applied and used along with effective.
However if you want to get heavy in melee with them, then Ironclads if you want PURE melee but Vens work too if you want some heavy weapon options for when walking across the board. Going for the stormraven drop, same applies really.
However the main thing to remember is you want to make sure to have extra units around to help intercept any shots, by that I mean be closer than the dreadnought. I mean, an Ironclad charging with this I believe would have 6 attacks (because they get +1 attack from the stratagem don't they) and if melee mode then gets raw re-roll 1s to hit. And hey, take the ironclad launcher thing and attempt to get them extra mortal wounds.
I Chapter Master 454, Chapter Master of the Angels of Justice, Warboss of WAAAGH Gubskul, Commander of a Catachan Regiment, Phaeron of a Tomb World, Shas'O to a Cadre and Princeps of a lance of House Taranis hereby pledge that I will not take up any further models til all other prior have been fully built and painted to tabletop standards. There is no time limit for this task, there is no deadline. My oath is to solemnly complete the armies I have now, to see it that they can have their glory. Paint will be stripped from the old in need, thick may it be like ceramite I will see it removed so that plastic and metal alike may see light of new paint. Models yet to be, boxed and in darkness will be assembled with due care and attention. For this task I am permitted to still buy the supplies needed to do my task but not one model more.
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