Somewhat surprisingly, the latest Warhammer 40,000 campaign book, provides a lot of new options to Space Marine armies. It primarily adds to the White Scars and Raven Guard Chapters, but the Formations included can be used by any Space Marine army. I'll be covering all of these new additions, starting with the new White Scars rules.
Scarblade Strike Force
The White Scars Chapter Tactics are fortunately unchanged. However, they've gotten their own Detachment, similar to the Gladius Strike Force. It's called the Scarblade Strike Force, and it allows most of the same Formations as the Gladius. It also adds a few new Formations that accentuate the speed (and Chapter Tactics) of a White Scars army. Unlike the new Formations, all units in the Scarblade Detachment have to be drawn from the White Scars Chapter.
The Scarblade comes with it's own set of Command Benefits. First off is Lightning Assault, which allows all units to re-roll failed Initiative tests for Hit and Run. This is a pretty minor addition, but it does add some extra reliability to the army. It's not common, but I've seem some battle plans destroyed by an unlucky roll keeping an important unit locked in assault. The next benefit is Ride the Wind, which allows vehicles moving Flat Out and bikes that are Turbo-boosting to move an addition D6" and Fast vehicles and Flyers to move an extra 2D6". This is great for last minute objective grabbing, making a White Scar army even faster. Finally, there's Maximum Impact, which gives all units Hammer of Wrath if the make a charge from 8" or more away. If they already have Hammer of Wrath, then they get to re-roll failed wounds. This gives the army a bit more assault ability, which is something that White Scars are often lacking.
Overall, these benefits work really well for White Scars armies, and I'd say that they're about equivalent to the Gladius Strike Force's additional Combat Doctrines and Objective Secured. More importantly, the Scarblade Detachment allows you to take a lot more bikes than a Gladius, further benefiting from the base White Scar Chapter Tactics. However, they lack the ability to get free wargear, such as the free Transports available to the Gladius. I'm personally happy that they're phasing these sort of detachment benefits, as large amounts of free wargear or units feel very unbalancing to the game.
Master Rider adds +1 to your Warlord's Jink saves if he's equipped with a bike. This is a little limited, as it means that your Warlord has to be in position to take wounds from shooting. However, this means that you have a single model with a 2+ cover save, which is extremely durable. Your Warlord can tank even AP2 wounds, and simply Look Out Sir any Ignores Cover wounds. If your Warlord doesn't have a bike, he gets Deadly Ambush instead.
Deadly Ambush allows you to add or subtract 1 from your Reserve Rolls, which is really useful if you're taking any reserves at all.
Hunter's Instincts gives your Warlord Monster Hunter and Tank Hunter. These are both great as they pass on to the rest of the unit.
Hammer of the Khan grants your Warlord Hammer of Wrath, and allows him to inflict D3 hits instead of 1 if he already inflicts Hammer of Wrath. Not awful, especially since these will be S5 hits that re-roll failed wounds if your Warlord is part of the Scarblade Strike Force. However, they won't benefit from his armament, so the attacks will mostly bounce off anything with decent armor.
Unrivalled Hunter makes your Warlord substantially better in a challenge, giving him an extra attack and point of Strength when in a challenge. These bonuses will apply most of the time, as your Warlord can charge into a unit, challenge most upgrade characters and wipe them out, allowing extra wounds to spill over into the rest of the squad. Against tough characters, these bonuses will be handy as long as your Warlord is armed for challenges. If you're in a challenge against the enemy Warlord, you Warlord can also re-roll failed hit rolls.
Merciless Warrior allows your Warlord and any unit within 12" to re-roll the die for Sweeping Advances. This is really handy for your assault units, as it makes them much more likely to catch and wipe out any units that you defeat. The bubble makes this much better, allowing it to benefit a concentrated assault with multiple units.
Relics of Chogoris
The Relics of Chogoris can be taken in any White Scar army, in addition to the relics in Codex: Space Marines. This gives White Scars a lot more options than most other Space Marine armies.
The Banner of the Eagle is a Space Marine Standard that grants every unit within 12" Fleet and Furious Charge. Both of these rules are amazing for assault units (especially Fleet), and having a bubble is awesome for supporting a concentrated assault. For the relatively low price, it's essentially an autoinclude for any White Scar army with a substantial assault element.
The Glaive of Vengeance is what a power lance should be. It has the same dual profile, but is +3S AP2 on the charge and +1S AP3 at other times, and it's always master-crafted. Even when you're not charging, it's still better than a power weapon. On the charge, it's almost a power fist that strikes at normal initiative. Using Hit and Run, White Scars should be able to charge every turn if they want to. The Glaive is a bit pricier than a power fist, but has substantial advantages.
The Hunter's Eye gives its bearer and any squad he joins Ignores Cover. This is a huge ability in the current game, and has previously only been available to most Space Marine units via psychic powers. The ability to take it on any unit you want reliably is incredibly useful. Expect to see a character with The Hunter's Eye hanging out with Centurions or grav bikers.
Mantle of the Stormseer gives your Librarian Adamantium Will and the Psychic Maelstrom power, without affecting psychic focus. This reliably turns your Librarian into a short ranged Vindicator. If that sounds fun to you, the Mantle is worth taking.
The Scimitar of the Great Khan is basically a Master-crafted power sword that gives +1S. When fighting in a challenge, the bearer gets +3WS. Certainly not awful, but not enough to deal with most characters that you would need to kill in a challenge.
Wrath of the Heavens is a bike that allows the rider to Turbo-boost 18" and pass over units and terrain as if it were a jetbike. While the idea of a Space Marine ramping his bike over enemy units is undeniably awesome, it is limited by the fact that he can only make use of it when alone. However, a Chapter Master with artificer armor and a storm shield is tough enough to run on his own, at least for a turn or 2, and the Wrath of the Heavens will give him a ton of mobility to reach important targets. It's barely more expensive than a standard bike, and almost certainly worth it.
I really like the new options for the White Scars. They allow you take take a very fast and maneuverable army, leaning more towards assault than your standard Space Marines. While the White Scars already had arguably the most powerful Chapter Tactic, none of the additions here feel over the top. They just allow for a different style of army than can be fielded with the Gladius Strike Force.
Of course, to really see the flexibility of the Scarblade Strike Force, we need to talk about the Formations that make it up. But that's next article.