Heroic abilities

**What do you want to see?**
Heroic Abilities would be a new type of ability that can provide a passive effect or activate on a cooldown, but are stronger than regular abilities and can only be possessed once per vehicle (no duplicates, no matter how many times it's granted). For instance, evasive maneuvers that give a temporary evasion bonus in combat. They would have prerequisites that would apply to a vehicle, such as a combat speed of at least 4, or belonging to an empire with the Organic racial trait, or having at least 500 experience points.

**How would it help players?**
Add more tactical depth to combat, sort of like Dominions spells

**Alternatives**
Could be just regular abilities (or weapon capabilities, which really should be abilities anyway) that are have prerequisites for being active.

**Screenshots and mockups**
N/A

**Things to consider**
???