Earlier builds featured an ability called Null Void.
Ability Cost: 50
Prevents any unit caught in the target area from using abilities that cost energy. It does not affect abilities such as a stalker's Blink, a carrier's Build Interceptor, a Phoenix's Overload or an SCV's Repair. Immediately upon exiting a field a unit can use its powers like normal.
Nullify acts as a detector, decloaking units such as ghosts and dark templar and revealing burrowed units. The ability to detect cloaked and burrowed units was being subjected to balance testing.
As of February 2009 the nullifier lost the Molecular Disruption ability.
The nullifier fires a psionic projectile which bounces between units of the same type, to a maximum of 10 bounces. (It deals 10 damage per "bounce"; 100 damage in total.) It can strike a single unit more than once.
In one of our Battle Report considered replays, I have actually seen 2-3 Nullifiers brought straight into the enemy resource line, then all exits force fielded so the enemy drones couldn't get out, and the Nullifiers pretty much killed a large amount of them easily since they get bonus biological damage. Karune. 2009-05-01. Worker harassment with Nullifiers. Battle.net StarCraft II General Discussion Forum. Accessed 2009-05-01.
↑Mothership has currently Time Bomb, Vortex and Cloaking Field abilities. Cloaking Field as a passive ability cloaks ground units and structures nearby Mothership. <b/>Archon does not have energy and energy-dependent ability.
Nullifier currently has Force Field and Hallucination abilities. Cydra. 2009-02-19. Cavez: quick questions. Battle.net StarCraft II General Discussion Forum. Accessed 2009-02-19.
↑ 13.013.1The Molecular Disrupter is a new ability we are testing out on the Nullifier, in which the unit fires a psionic projectile which bounces between units of the same type, doing 10 damage with each hit, up to a maximum of 10 bounces. Thus, if you were to use this ability on 2 Marines (with 40 hit points each, not upgraded), both Marines would die easily. If there were 3 Marines, it would kill 1 Marine and leave the last two at 10 hp each. Currently, the ability costs 125 energy. Karune. 2008-10-20. Karune: Molecular Displ. & Seismic Thumper?Battle.net StarCraft II General Discussion Forum. Accessed 2008-10-20.