Augmentation

"You can use your power to amplify mine."

- Christy to Billie.

Augmentation is the ability to make the powers and abilities of oneself or another stronger. Augmentation has never been shown to be an active power, but merely a skill various being learned after the exploration of the capabilities of their powers.

However, it is an extremely rare and powerful ability as it allows the user to makes their powers stronger and themselves more powerful. Witches have been known to use spells and potions to enchance their own magic.

Powers
Billie Jenkins learned to use her Projection power to enhance another person's power. She used this aspect, only once, to strengthen her sister's pyrokinetic power, so that they could vanquish a demon thought impossible to be vanquished.

The power of Empathy can and will automatically strengthen and evolve any other power the user possess if they cannot turn their empathic power off, since all supernatural powers are tied to emotions.

Prue Halliwell, during her brief time as an empath, effectively had the entire rainbow of human emotion under her belt, and to extreme degrees. This exceedingly high inflow of emotion granted her a massive power boost, to the point where she became more powerful than the thought invincible demon, Vinceres.

Her telekinetic power was the first to advance, to a point where Vinceres, a demon who was immune to witchcraft, became vulnerable to it, and even allowed her to perform gravity-defying maneuvers so that she could meet Vinceres blow for blow in classic hand-to-hand combat. It also evolved her power of Astral Projection into Cloning.

Environment
Magical beings can enter and leave Limbo by using water as a portal. In Limbo, those with powers will find that their abilities have automatically increase in strength or have evolved into new abilities.

When Paige Matthews entered limbo her telekinetic-orbing power automatically advanced, allowing her to orb an object and her sister's soul, without calling for them. When Yen Lo, Phoebe Halliwell and An Ling entered limbo their levitation power did not advance, it evolved, into Flight.

Spells and Rituals
Prue Halliwell once casted a spell to triple a witch's strength in hopes of multiplying her telekinetic power.

Potions
P. Russell once tripled the strength of her pyrokinetic power through the use of a potion made by the warlock Anton. The potion made her stronger and advanced her power into Fire Throwing, which she used to fight off her cousin's Cryokinesis power.

Artifacts
Shuvani's and other beings in possession of The evil eye, an ancient Gypsy talisman that is blessed with the ability, augmentation, can use it to augment their own abilities.

Lydia Nicolae owned the necklace and used it to augment her power of Optical Thermodynamics; the power to shoot green beams of energy at an opponent.

In early 2002, Phoebe Halliwell was experiencing problem with her power, her power Premonition was inactive and she could barely levitate. However, as soon as she touched the tailsman, her powers became active once again, and even advanced allowing her to experience the event as she astral projects into her future self.