Though the term Veteran Squad can refer to any number of groups of experienced soldiers gathered in a single unit, in the context of Warhammer 40k this almost always means either the Hardened Veteran squads of the Imperial Guard (Read: actually survived a battle) or, more frequently, the squads consisting of the most experienced brothers of a Chapter of Space Marines.
Consisting exclusively of members of the Chapter's First Company, Veteran Squads consist of three different kinds of Battle Brothers: the Terminators, the Sternguard Veterans and the Vanguard Veterans. Though these groups maintain a sense of rivalry with one another, on the battlefield they are a lethal and efficient force.
The Sternguard are Tactical Marines cranked up to 11. They are the masters of the Bolter in all of its forms (In fluff, in the Crunch they have the exact same Ballistic Skill): from a standard Bolter to the Storm Bolter to various kinds of Combi-weapons all the way up to the Heavy Bolter. They are also trained in the light support weapons used by Tactical Marines: the Flamer, the Plasma Gun, the Meltagun and the Gravgun. They are also one of the few squad types entrusted with Heavy Flamers.
Aside from the standard issue Bolt round the Sternguard Veterans are equipped with a number of different and specialized Bolter rounds:
- Dragonfire Bolts are designed to explode into a superheated gas to tell any form of cover the enemy is in to go fuck itself.
- Hellfire Bolts replace the projectile's explosive payload with mutagenic acid, designed to combat the Tyranids and all sorts of big non-vehicle targets.
- Kraken Pattern Penetrator Bolts are improved rounds with a better range and penetration.
- Vengeance Bolts are more or less miniature plasma grenades that violently explode upon impact, but are a danger to the user as well. These were designed to combat the Chaos Space Marines.
Though the standard equipment of the Vanguard are the Bolt Pistol and Chainsword, they have access to the Chapter's armory to become even deadlier in combat. The most commonly used equipment for the squad consists of twin Lightning Claws and the Thunder Hammer/Storm Shield combination, depending on what the mission calls for. They are also equipped with a selection of grenades.
Their "Heroic Intervention" rule used to let them assault out of deep strike, but needed to be declared they were going to try before placing and rolling for scatter. This has been changed so that they ignore disordered charges, and their sarge auto passes the test for a Glorious intervention.
In 7th, they still ignore disordered charges, but no more auto-pass Glorious Intervention tests: they can now re-roll dice for charge. Which, if you have Jump Packs, is pointless, as you can already re-roll charge. (Which is why you use the jump packs in the MOVEMENT phase.)
On the Tabletop
Both Sternguards and Vanguards were significantly retooled for 8th Edition. For starters, the Sternguard no longer have their four flavors of Bolter rounds: instead they get a Special Issue Boltgun with 30" Rapid Fire 1 S4 AP-2 D1. While a significant downgrade from what they used to have, it is still a superior Bolter. This, and the LD of 8 instead of 7, makes for the main difference between the bare Sternguard and Tactical Marines, which comes with a price tag of 18 points instead of 13. It's when you look at the upgrades when they start to shine. For starters, a five-man Sternguard squad can pick two Special or Heavy weapons, including the Heavy Flamer while a ten-man Tactical squad can pick one Special and one Heavy weapon. But the real fun begins when you realize that everyone can replace their Special Issue Boltguns with a weapon from the combi-weapons list. This includes the Storm Bolter, which doubles the fire rate of a regular Bolter (but loses the improved range and AP of the Special Issue Boltgun, so it's not worth it), but more importantly the combi-flamer, combi-plasma, combi-melta and combi-grav. These are not by any means cheap (starting at 11 for the Combi-Flamer), but when you realize that these guns can be fired in addition to their Bolters, and that flamers hit automatically means that with Combi-Flamers the Sternguard is now capable of devouring entire infantry blobs at a time. Furthermore, ALL Sternguard in a unit can take combi-weapons, not just the four initial ones running with the sergeant (who can take one too). Can you say 10d6 hits from flamers alone? If you're feeling lucky and are willing to stand close to your opponents, you can give them all combi-plasmas to act like a cheap Hellblaster squad, but don't use them against TEQs.
Vanguard Veterans do more or less the same. Meant for assault, the Vanguard cost only 18 points bare with Jump Packs. At that point you start slappong on the special weapons. A combo of Power Sword/Storm Shield only sets you back a modest 27 points a model for something with a 3++ save that chops up power armored enemies with ease. An alternative is using a pair of Lightning Claws: while a bit more expensive it nets you a reroll to failed to wound rolls and +1 Attack. This is especially useful against Nurgle worshippers, and if you're feeling lucky they might be able to finish a damaged vehicle under T8. Very expensive, but also very lethal, is to give everyone Thunder Hammers. Almost doubling your points, it allows your Vanguard to reliably kick holes in tanks with S8 AP-3 D3. Sure, you'll only hit on a 4+, but it's hilarious when you manage to beat a Monolith into dust.
When using Power Ratings the Sternguard become even crazier: you now no longer have to pay out the nose for those expensive combi-weapons. Slap on a series of Combi-Gravs and watch them devour entire squads of Terminators. 7 Power is a bit expensive for a small and relatively fragile frame, so do keep them protected.
The same goes for the Vanguard: 39 points is a lot for a one-wound model with a Jump Pack, Thunder Hammer and Storm Shield, but for five Vanguards armed like that when using Power Rating it's the same base 7 power. This makes them hilariously scary when used properly, beating up enemies left and right while being annoyingly durable thanks to their 3++. They're not invincible though, so use them with care.
Tyrannic War Veterans
After the Battle for Macragge, the Ultramarines formed the Tyrannic War Veterans from the survivors of the battle Companies. Trained by Ortan Cassius, their sole mission is to exterminate all Tyranids. They are more or less Sternguard with a bit of Deathwatch-light training thrown in to kill Tyranids as quickly as possible.
Tyrannic War Veterans "are" actually part of the first company, though they take their orders directly from Chaplain Cassius. They are a select group of Veterans from all companies that survived the Tyrannic Wars, but since they act as a separate unit from the rest of the chapter's organisation this meant a bit of deliberation over the Codex Astartes on the part of Marneus Calgar before they could be deployed. They all carry relics of the fallen first company, wearing armour pieced together from the previous 1st company veterans, and carrying their old bolters which they load with Hellfire shells.
They also don't recruit new members, and number only a few dozen, which will inevitably decrease over time and be replaced with "standard" 1st company veterans.
Also, with the Tyranids Codex being the shitfest it is, the powers that be decided to drop in a Dataslate for the Tyrannic War Veterans, being a special formation whose existence is akin to kicking a dying puppy.
Since all of the Dark Angel's first company veterans who would normally make up the Vanguard or Sternguard units only deploy in terminator armor they don't get either. Instead they get "Company Veterans Squad". Literally veterans of whatever company they're in rather than the first. While not singularly specialized for ranged or melee like Sternguard/Vanguard, lacking specialist ammo for shooting, and jump packs for assaulting, they have the option to mix and match melee and ranged into the same unit, giving them some good versatility. They're also cheaper, as compensation for not having Special Bolter Rounds.
Command Squads have been axed in 8th and rolled into Company Veterans. Including the ability to take Bikes for a cost, while Champions and Apothecaries are taken separately. Dark Angels can upgrade to Combat Shields without having to give up one of their weapons. Making them the best choice for Green Wing armies, or can be meats shields for the Imperial Space Marine. With the buffs to Plasma weapons and Combi-guns, its not like DA players weren't already taking them for more Plasma spam. Admit it, you were already guilty of this or considered doing so.