Willpower Induction: Ion has infinite or omnipotent Willpower-casting powers and abilities.
Connection: It can make a connection with someone who has incredible willpower or is strong in their beliefs.
Time Manipulation: Omnipotent ability to control time.
Reality Manipulation: Omnipotent ability to control reality.
Willpower-Induced Energy Manipulation: as the embodiment of willpower (Ion Power), Ion can control, manipulate and generate green willpower energy. All powers similar to a Green Lantern Corps Power Ring and the Starheart.
Immortality: as an entity based upon an emotional concept, Ion is unending. Exists forever.
Protective Aura/Sheath: endows its host with a relatively permanent personal force-field that protects its host from bullets and the like (described as “invulnerability”). This life sustaining aura protects the host from harm. Ion can generate a field of life sustaining atmosphere and protection from harmful radiation, even if the host is unconscious.
Flight/Levitation. The ability to move freely via ones mind or will through atmospheres or space.
Psionics: Unlimited psychic powers and abilities.
Create Solid Light-Energy Constructs.
Since the power is based on the beings imagination, Ion's (and its host) powers and abilities are virtually limitless.
When Ion is attached to a Green Lantern all their abilities are amplified at an exponential rate. It may have been mentioned that the Living Lantern (Ion) becomes so powerful that things that would seem too difficult or great are done with the slightest ease.
It's power is virtually limitless depending upon only the wielders own imagination.
The Ion entity, as a sentient being composed of pure will, can presumably be distorted by other entities of the Emotional Electromagnetic Spectrum that the green light is weak to. However, like Green Lantern power Rings, the Ion entity has been shown to be able to affect at least the yellow light of fear, and even force it to become Green energy. Its effects on other energies of the EES have yet to be seen.
Without a host, the Ion Entity is shown to either be impotent, or at least unable to access the full range of its abilities.
Ion has more powers
Nova Force has Richard Rider.
Two extremely awesome things
The original Ion was much more powerful than the Nova Force...but I chose the NF because I like it better now that Rayner isn't Ion plus Nova Prime was BA.
Well, even when Rayner possessed Ion entity (not total energy of central battery like HoG), he isn't that powerful, a few Yellow Lanterns are capable of overpowering him and Superboy Prime almost killed Ion-possessed Sodam Yat with nothing but fists.