From the advent of the third edition of Warhammer 40,000 in 1998, the field leader of choice for Space Marine armies has been the Chaplain: standard-equipped with both an armour-negating power weapon (in his Crozius Arcanum) and invulnerable save (in his Rosarius)—the first purchases other HQ choice Characters regularly made from the Armoury—a Chaplain rarely required more than the investment of another point for a bolt pistol and he was ready to lead on the tabletop...and lead from the front!
40K V5 adds some extra considerations and caveats to that general principle—not least of which, the 'powering down' of the basic stat line suffered by both Chaplains and Librarians in this new edition—but Chaplains remain an excellent HQ choice nevertheless, especially for beginning players or players looking to keep their Character/HQ expenditures to a minimum, in favor of other unit choices.
CHAPLAIN CASSIUS
The new Codex: Space Marines provides only one Special Character Chaplain template—but it is a good one: for only ten points more than the cost of the closest similarly-equipped generic Chaplain build, the Cassius template gives a player the Infernus wargear (a mastercrafted combi-flamer loaded with special Hellfire rounds), plus the excellent Feel No Pain universal special rule and—perhaps most significantly—a superhuman (even for Space Marines!) Toughness of 6. These latter represent in the specific Ultramarine Character Cassius the extensive bionic rebuilding he underwent, and players looking to build their own Chaplain on the Cassius template should consider how (via their background or choice of model) to explain their Character boasting such similar incredible statistics. Cassius nevertheless represents *such* a significant upgrade over the generic Chaplain for the points that I expect to see a great many hobbyists undertaking that effort.
All Chaplains lead best from the front, Cassius even more so...though it should not escape mention that his artifact combi-flamer Infernus makes him far 'shootier' than most, as well. An almost ideal deployment for Cassius would be in company of a unit of Sternguard, perhaps deployed against a high-value target via Drop Pod. Adding a Cassius-templated Chaplain to the kind of elite, Sternguard-dominated army led by a Kantor-templated Chapter Master (as discussed in Part One) would be all kinds of nasty...
A Space Marine player looking to get as close to the same kind of 'oomph' with a Chaplain HQ choice as he is used to, from prior editions, should examine the Cassius template thoroughly. The Infernus' mastercrafting will even compensate for the loss of Ballistic Skill. Whether as a supporting second HQ choice, or a good-value-for-the-cost single one (the Chaplain's traditional role), Cassius delivers.
CHAPLAIN
The virtue of choosing to equip a custom Chapter's Chaplain from the generic HQ entry is, of course, that the creating player is not locked into Cassius' weapon choices, nor limited by what he eschews. The Infernus is good—but does not provide the additional Attack in assault a bolt pistol does. And Cassius has neither a jump pack nor bike nor terminator armour...all of which can serve to either streamline or emphasize what a Chaplain should be doing, to take best advantage of his special rules: charging into close combat. Jump packing Chaplains leading Assault Marines are practically staples of many Chapters. And 25 points is still 25 points—especially relevant since, as noted, basic Chaplains tend to be the HQ preference of players wishing to invest maximum points in other parts of their army.
Finally, the generic Chaplain requires no thinking or modeling to justify Toughness and Feel No Pain—he has just ordinary superhuman Toughness, rather than extraordinary—all of which make the option a good one, still (though any consideration of taking a plasma pistol with the V5 Chaplain's reduced Ballistic Skill and loss of access to mastercrafting becomes the preserve of the true gambler).
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