Team builds? We fucking love team builds! Here's the Modular Deathball.

Introduction:

In Starcraft parlance, a deathball is a close packed group of units that move across the map in a blob, annihilating everything in their path. Here, we can only make a deathball of four, so each part needs to be chosen carefully. Fortunately, once we notice the basic idea, we can begin to swap some parts out, while keeping the power of the deathball intact.

The theory:

The goal of this team is to get every member to have a high DR while maximizing offensive damage output. This can be done in two ways. First, spread out DR among the team, so every member has their own DR of about 40%, with one player making up the rest. This way gives some flexibility in play-style, but reduces offensive output: everyone is using a DR power, so recharge is limited, and points are not put in offence. The second way is to concentrate the DR into two players, freeing up the other two to focus on pure offense. This maximizes point and damage efficiency at the cost of requiring a certain play-style: the team needs to stay close, so the offence and defense can keep each other alive. This, of course, is the deathball style, so its what I'm focusing on.

The build:

Defense: Volus Adept, Asari Justicar

Rank 6 of shield boost gives 50% DR, the sphere gives 40%, handing out an excellent level of DR. The Volus is spec'd for pure recharge speed, but swapping our the structural ergonomics for a pistol amp won't hurt too much (.1 second difference) and adds some more punch to the shield stripping he should be doing in between casting shield boost. The justicar is more of a hybrid, with a full defense sphere, area reave, and AR weight reduction to allow a harrier. This alone gives a decent amount of punch to the team, but we can do better. Much, much better.

Offense: We have more flexibility here, since we already have 90% DR. Now, we just need to find the best way to optimize killing power between two other characters. And if we can even further increase survivability, why not?

Option one: Kabloomers Vorcha Sentinel, Turian Ghost

Who would have thought combining broken classes with broken guns makes things broken? The idea here is to get biotic and fire explosions every three seconds or so, while maintaining withering harrier fire the whole time. Cluster grenade detonates reave, while not affecting the flamer cooldown, and overload combos perfectly with flamer: detonating it while knocking out shields. Moreover, the vorcha keeps its health high, since it will get a large portion of kills, and the ghost's cloak adds extra versatility and survivability to an already tough team.

Option two: Tank harder, tank smarter Krogan Shaman, N7 Destroyer

More broken classes, only one broken gun. Both guns, however, are designed to prime large groups for being detonated with reave and shockwave, so pick your ammo accordingly. This set up also maximizes shields on the offensive side of things. One casting of shield boost won't fully restore the shields on these two, but since the sheilds-per-second bonus lasts 3 seconds and the cooldown on boost is less 2.8 seconds, they should always be getting 160 shields per second, with a 640 point boost every 2.8 seconds. With the 90% DR, this is alot of damage negated.

Wrap-up:

I've only given two variations here, but there's so many more possible that I'm certain I've missed the optimal group of four. With this rough framework, though, putting together a group that hits the high points of the build, team-wide 90% DR, lots of firepower, etc, that works with your available inventory shouldn't be too hard. I also haven't talked much about tactics, but that's because they're fairly simple. Stick together, keep the sphere and boost going, then murder anything in range. The flamer based combos work best when using clever positioning that funnel enemy groups into chokes while keeping long-range enemies from having a shot. The tankier combo only needs good LoS to keep firing.

There's also alot of flexibility on the weapon/power choices. Harriers can easily be swapped for mattocks, and if you feel you can keep a tighter knit group, radius evo's can be changed out for more effect-based evo's. You clever devils should be able to come up with legions of possibilities that push the potential of this sort of build ever higher. I'd love to see what you come up with that I didn't even consider.

Edit: Turns out, my basic assumption was wrong, but not catastrophically. As mentioned by very helpful members, DR doesn't cap until 133%, so there's yet more room to grow. Based on information here, the magic value for damage immunity is 133%. I have no real desire to make a whole team damage immune, so the build listed in my reply to Republican Shredder gives a listed DR of 130% to three of the four members, while the Volus is stuck at the original 90%. Its hard to get a value for real DR (especially since the formula listed in the link will never produce a damage value of 0, yet damage immunity based on DR is possible), but being 3% off of the value that grants immunity can't be bad. As for the original suggestions, I stand by them as being an excellent blend of tanking and firepower, if not as immortal as my original numbers suggested.