Jwolf here. 40K in Fifth Edition is a war of maneuver above almost all other considerations, thanks to the improved survivability of vehicles, the prevalence of Reserves, the ability to Outflank, and, most importantly, the objective-based nature of the game. Almost every Codex has some great tricks to slow down enemy movement and limit LOS to important targets: I will discuss some of these tricks below.
Rhino / Chimera Walls. The Imperium has a significant advantage over the Xenos in their ability to flood the battlefield with the movable terrain known as Rhinos and Chimeras. The obvious use of the wall is hiding more valuable target behind it, including other vehicles. Rhinos and Chimeras also are great for blocking off objectives; with good positioning, you can prevent even Skimmer tanks from being able to Tank Shock your infantry without first needing to successfully destroy the transport blocking their line of advance. I’m also a big fan of Jump Infantry moving up behind pairs of Rhinos.
Besides the defensive uses of Rhino walls, they are great for stopping that Land Raider full of Assault Terminators from crossing towards you too quickly as well. Just run a couple of Rhinos right into the face of the Land Raider – at less than 3” the Land Raider only hits you at Strength 5, which means you are probably going to be undamaged and you certainly cannot be destroyed, so the Land Raider has to go around you, wasting a turn of movement.
Skimmer Squadrons. Light Skimmers are excellent maneuver blockers, as they have the Skimmer Save against ramming, which means that only a desperate enemy will try to ram them instead of just going around. A Squadron of Speeders / Vypers / Piranha can effectively prevent any forward movement in one area of the board, so consider a cheap Squadron as a blocking unit.
Medium Skimmers. A pair of Devilfish or Wave Serpents gives you a very effective maneuver restriction against all terrestrial units. The single exit points mean that you must be careful about getting too close and letting the enemy get into the rear, if you have units inside, but otherwise, these are great blockers.
Large Skimmers. A Valkyrie has such a huge footprint that even Skimmers have a hard time getting past them. I would expect the Storm Raven to have a very similar footprint, which means that two of the best Codices also have to of the most maneuver blocking units. And don’t forget the Monolith, which has, in addition to a huge footprint, extraordinary defensive ability to add to the party.
Land Raiders. Land Raiders are the ultimate screening tool of the Imperium. You can drive a Rhino completely hidden behind one, and screen vast amounts of troops with them as well. A Land Raider is nigh-invulnerable until within 6” for most units in most armies, so it can cover you right up to the point where its deadly cargo bursts out to slaughter.
Drop Pods – one of the most annoying things that Space Marine players can do is dropping a wall of Pods to effectively divide an area of the board from the rest. Having to take the time to blow up the Pods can take all the steam out of an advance. Tyranid Pods have the added benefit of being able to destroy vehicles that try to tank shock them with their Monstrous Creature CC, and they are less likely to be used as free assault moves by infantry moving across the board.
Meltaguns – No one likes to get hit with Meltaguns, so be sure to place those in between the enemy vehicles and their desired location (between them and the objectives).
Bait units – Putting tempting units away from the objectives can put the enemy in the wrong position just as easily as blocking them. One of the best choices is pulling units towards board edges where anti-tank will be coming in and/or near strong assault elements. I have found that HQ choices are very hard for even veteran players to resist as bait units.
Fish of Fury – Okay, so the old Fish of Fury doesn’t exist anymore. You can still use vehicles, especially pairs supported by Light Skimmers, to get your shooters into position to kill the enemy and still safe from a lot of enemy retaliation.
Terrain – Some of the concepts of blocking are best reinforced by terrain. Blocking maneuvers are enhanced by areas of difficult terrain, so when you are placing terrain, keep in mind where you might need to create roadblocks (and where your opponent might do the same to you). This takes a practiced eye to do well, but even a novice can get the basic concept and put it into service.
I’ll do a battle report this week with some blocking maneuvers in it, to provide practical uses for these techniques.
If you have a roadblock technique you’d like to discuss, I’d be glad to hear it.