Marine codex 'review' (#6): sternguard

Sternguard: great.

No matter what your ranged needs may be, the sternguard delivers. Being essentially a unit of sergeants, their statline allows them to fight back against weakened units that get too close, and to win offensive combat against light infantry - should the need for a charge ever come up.
They have the ability to take two of all support weapons available to other marine infantry, at a very affordable cost. Multi-meltas, missile launchers, heavy bolters, plasmaguns, meltaguns, flamers, lascannons, plasmacannons - and heavy flamers.

Of course, there's also the 'special issue' ammo. This handy piece of gear is what allows the unit to deal with pretty much any and all threats out there, and it's available to anyone in the unit with a bolter or combi-bolter. Special issue ammo, combined with combi-meltas, mean nothing and no one is safe from you. You should always have at least 2 of these in the unit, and bring extra combis as points allow.
In fact, special issue ammo combines so well with the combi-melta, most of their support weapons end up looking useless, and - for the most part - they are. Some, however, are very worth your time, despite stealing your bolter and special ammo.

"What's so special about special issue ammo?" Simple. You get four kinds.
Kraken makes your bolters range 30 and AP4. This is the camping ammo, and it lets you outrange all except one kind of basic infantry in the game.
Hellfire is regular bolter profile, but poisoned 2+. It's a very, very, very good thing. So nightbringer has a toughness of 8? He's still wounded on 2+. Universal ammo.
Dragonfire is also regular bolter profile, but instead of wounding on 2+, it ignores cover saves.
Vengeance is shorter-ranged than a regular bolter (doesn't matter, since you want to be within 12, anyway), but is AP3. This means you demolish power armor. Yes, really. Also is 'gets hot!' so don't go crazy with it.

Need a position anchored? They can do that. Give them some lascannons or missile launchers, and they can snipe armor at long range.
Offensive shock troops? Check. If you're planning on using them for this, twin heavy flamers become a very, very good option. While special issue ammo lets you to hurt pretty much all infantry, it's only two shots per guy. A flamer template will hit many, many more, plus destroys most things not wearing power armor - and most that are, too, through sheer number of wounds inflicted. That's what you call 'crowd control.'

Never forget the mandatory rhino, for it is much of the source behind the sternguard's power. Putting matched lascannon sternguard inside one is another form of bunker, but this one has 48 inches of range, and likes sitting back with your predators.
Drive-by heavy flamer sternguard is lots of fun to watch, but not so much fun to endure, and completely missed by most people, due to there not existing a model for it.

The beauty of this unit is, no matter what role you decide to give them, their special issue ammo lets them do more.
For instance, the heavy flamer squad above can still take up position in a ruin somewhere, and camp distant enemies with kraken ammo. It can also actively hunt armor, since it brought a bunch of combi-meltas.
Lasbunkers are still capable of moving forward eventually, and rapid firing people to death with special issue ammo.

If you're feeling silly, you can replace your bolters and special issue ammo with stormbolters, thus making the entire unit pointless and more expensive. Don't do this, please.
No, not even for a 'themed' mister Kantor bodyguard.

Yes, you can take 8 combi-plasmas and 2 plasmaguns, but you don't want this, because combi-meltas instant-kill 'hard' targets (nobz, characters, tyranid medium critters), destroy armor, and let you charge afterwards.
Yes, you can drop pod and split 10 men into two units of 5 each, attempt to destroy two rhinos with all your meltaguns, then promptly die. No, this isn't worth the minimum 285 points ever, no matter how many times warseer tells you to do this, and is the number one reason not more players field sternguard.
Yes, a 925 minimum points investment buys you Kantor, 30 sternguard, and lets you play around with 6 scoring units. Oh my god, you're so cool and good, Kantor! Make my shooting units into scoring units, and improve their combat powers. Please, take away my ability to avoid combat, too, because I want my 250 point squads of 3+ save dakka infantry stuck in against imperial guard blobs forever.

Speaking of combat squads, quite unlike other units, both halves of combat squadded sternguard are extremely potent, and cannot be ignored by the opponent.
In large games, it's sometimes nice to take 10 man squads, split them in half, and drive the combi-meltas forward in rhinos/razors, while the lascannon part hangs back.

When tactical marines enter puberty, this is what they become.
Sternguard are extremely good value for the points - the base squad costing only 35 points more than 5 tactical marines - and the most flexible unit in the codex. Not fielding them is a criminal offense, and should only ever happen because you need extra dreads, assault terminators, or happen to be running a themed list.

An essential component of 5th edition mechanized marines, bringing massed melta, cover-busting guns, armor saturation, mass templates, and long-ranged weapons - you simply want these. Easily the best utility unit in the codex, and had mister Kantor made them count as troops, he'd have been a good pick.

What makes it good: if you send properly kitted sternguard into a firefight, you win. Case closed. Also brings multiple heavy flamers regardless of squad size, and knows how to use them. Multi-lascannon, too, and 100% melta, should you desire it. Their high threat rating lets you present baits that the opponent is almost guaranteed to leap at.

What makes it bad: almost suicidal. The opponent learns quickly to fear these, and will destroy them fast, unless you bring deadly unit saturation - which isn't that hard to do with marines.