Character Guides - Brooks - Onslaught/Conquest/Heist preset - May 30, 2020
Space-Time Rend - Brooks adds 4 Black Holes around him that end with Explosive Evaporation
Brooks' Onslaught/Conquest/Heist preset is a defensive keepaway build. Crossguard, Blastback and Black Hole are all designed for Brooks to keep his distance as much as possible, and Brooks can gain more Extreme with his attacks and abilities against enemies caught in a Black Hole (that is not part of Space-Time Rend).
Despite Brooks' good Attack stat, he plays primarily on defense in Onslaught/Conquest, in the form of keepaway. His only real source of damage is his Black Hole, especially Space-Time Rend's end, where the Explosive Evaporation does large damage to all enemies caught in the Black Hole(s).
When playing Brooks, use Crossguard if enemies swarm him to build Extreme and launch them away, and get enemies caught in his Black Hole. Blastback is both a good escape tool and an Extreme builder if it hits enemies caught in a Black Hole. When going into Aim Mode to use Brooks' basic attacks, do not spend the whole time there -- it can be difficult to see reinforcements or cars approaching, and Brooks will need to reposition frequently and use abilities outside of Aim Mode, anyways.