I no longer remember what exactly this ability does, though I seem to remember something about it consuming all in its path. But yes, I suppose it is cool.
Grey Goo was an ability I designed that could only be applied to a unit either without shields or with it's shields down. Once inside the shields, the DoT begins to fork and the DPS taken by the ship skyrockets. Also, any nearby ships also get hit by it if their shields are down. When the ship ultimately explodes (I made it so that only Repair Cloud could save the infected ships, though you'd have to be ready to spam it repeatedly), it infects a larger radius of ships regardless of whether or not their shields are online. As a result, once a ship gets hit by it you send that ship on whatever course it's on and have everything else run for the hills.
So yes, Grey Goo does consume everything in it's path.
In other words, the hard work.
Lol, this was really quite easy, likely because I'd already been thinking of the possibility of sticking various passive abilities on the fifth slot of every ship and what that could allow.
The first thing that comes to mind is the ability to establish hard-set synergies between ships. For instance, the Radiance, Progenitor, and Halcyon could collectively have AoE buffs that when return to themselves with the buffs from the others, super-buff that particular unit, creating the "Holy Trinity." Likewise, you could make a "Dark Triad" (or whatever you want to call it) out of the Revelation, Rapture, and Discord.
Each object in the game would have an ability called AbilityIs____, so AbilityIsProgenitor, AbilityIsRadiance, AbilityIsHalcyon, etc. AbilityIsProgenitor for instance would then apply things such as BuffIsProgenitor and BuffIsAdvent.
BuffIsProgenitor would apply buffs to all nearby owned capitals and would test them for BuffIsRadiance or BuffIsHalcyon. If a ship receives the buffs from all three, it receives something like BuffHolyTrinityProgenitor that'd do all sorts of things to AM regen or what have you.