Strictly speaking, Guidance isn't totally necessary, unless you want to repeat that combo in a shorter time.
Amplify Energy Aura decreases Advent weapon cooldown (not abilities), so ships firing their standard weapons use this bonus.
The Malice+CB combo is an old one, somewhat less effective since Malice's duration was shortened, but still has devastating effects against a tight cluster of ships. Optimal result is achieved when Malice is in effect during the time CB is being used in order to propogate the full 2000 damage each affected ship recieves during the 8 seconds CB is active.
Vengeance targets a friendly ship, not a hostile one. The ship affected will return a certain percentage of damage it takes to the ship that originally dealt that damage (damage returned is 65%/130%/200%). Best used on a Radiance that has used Animosity to force surrounding enemy ships to fire on it.
By far, the Advent have the best synergy with their abilities, but that doesn't mean combos with the TEC and Vasari aren't possible. Volatile Nanites from a Kortul paired with a Vulkoras using Phase Missile Swarm can cause a chain reaction when one or several ships are destroyed, the resulting explosions damaging nearby ships causing them to be destroyed, causing further ships to be destroyed, and so on.
