Molecular Combustion

Molecular Combustion is the power to speed up molecules to the point that they combust. It is an advancement of Piper Halliwell's original Warren-witch power of Molecular Immobilization. It is an extremely rare power, is the strongest offensive power possessed by the Charmed Ones. Piper picked this up shortly before Prue's death, making Piper the most powerful of the Charmed Ones. Piper channels this power through similar gestures to her freezing powers.

History
As with most new powers, this power could only be triggered through emotions. In this case, anger and frustration. On top of that Piper lacked any precision or restraint over it. This led to Piper being afraid to use this power, as she never knew if the target would freeze or blow up. This was first seen in Piper's battle with Tarkin, who she unintetionally vanquished with this power, while her original intetion was to freeze him.

Not long after this, Piper and her sister encountered a Banshee. According to the Book of Shadows, there was no known vanquish for the Banshee. Piper soon confronted the Banshee in the attic, not knowing what to do, Leo suggested that Piper blows it up. She believed that she couldn't, but ultimately did, making this the first time she's intentionally used this power. Very shortly after those events Piper tried to use it on Shax, the personal assassin of the the Source of All Evil, but he was far too powerful to be vanquished by it and was merely repelled.

Years later, Piper is able to control the strength of this power, using it to knock Christy down without overly harming her. This power is more tightly linked to Piper's emotions and dangerously so, as seen during an argument with Leo, Piper was able to blow up an entire door and part of a wall in the manor. This is the last power used to vanquish a demon on the series: Piper uses it to blow up past and present Dumain, vanquishing both with one hit each.

Strength, Control, & Development
When Piper first received this power, it alternated unpredictably with her freezing power, especially after the death of her older sister, Prue. The reason being, her emotions were very of balance, causing her powers to be highly unstable. After she recovered from Prue's death, she began to practice her power, and as time went by, Piper relied less on her emotional triggers to activate the ability and grew more confident in using it. She became more precise with it, allowing her to reduce her foes to ashes with the mere flick of a hand. With her immobilization power she could selectively freeze, she is able to replicate this through her combustion power, with the only difference being, she can target the individual body parts of a demon, blowing them up. Piper also learned to control the strength of her ability varying between destroying a single target. Piper has also been shown to destroy multiple targets in quick succession.

Early on, this power was formidable enough to destroy exceptionally powerful upper-level demons. For instance, Tarkin, the first demon to fall victim to this power, was only slightly less powerful than Cole's demon half, Belthazor. Previously, it was thought he could only be vanquished with a potion that contained either his flesh or the flesh of another member of the Brotherhood Of The Thorn.

When Piper gets emotional she loses control of the power, as seen when she and Leo were having marital difficulties, as the power is heavily tied to her emotions. When Leo walked away from her during an argument, she unintentionally destroyed the door he had just walked through. Though, the more emotional Piper gets, the stronger her power grows but also the more uncontrollable it is, when she blew up the door unintentionally she used one finger that shows the magnitude of power is greatly enhanced when she is overwhelmed with a lot of emotions.

Piper can also manipulate this power to create a telekinetic like effect to push demons away and knock them off their feet. She can create ripples in the air that thrusts the demon backwards like she did in season 7 after she blew up an energy ball. Piper, disguised as Wyatt, blew up an energy ball, and by continually combusting the air around it, guided it into another demon. In that same episode, she also froze an energy ball and by hitting the demon at a certain angle, made him get pushed into the energy ball, vanquishing him. She can also control how powerful she wants to make the power.

Piper can also manipulate this power in a form of Deviation, combusting the molecules surrounding a projectile and redirect it or reflect it back at an attacker. This appears to prevent Piper from being struck with the debris from her own attack.

Eventually, this power grew to the point that Piper could destroy upper-level demons that were thought to be practically unvanquishable, such as Jeric, a powerful ancient Egyptian demon. Jeric was so strong that his Egyptian foes could only mummify him, but Piper destroyed him with one hit.

By her eight year of being a witch, Piper had grown powerful enough that she was able to blow up Baliel, a member of The Triad, with three hits to the chest. Previously, the Triad had been thought to be practically unvanquishable by witchcraft. However, Baliel's power had been significantly reduced when he accidentally vanquished one of his compatriots, thus weakening the collective.

Immunity
However, other beings have been shown to be immune to her power, being only knocked back a few feet, only have certain body parts destroyed or manage to reconstitute themselves - such as The Source of All Evil, Kurzon, or Cole Turner. The Source and Cole both were reconstituted when Piper attacked them with this power.

However, it seemed to have different effects on both, with the Source's just spiting in two and rejoining again while Cole's molecules broke up and were entirely undone until moments later.

Other Users
This ability can be difficult to control and takes much concentration. Wyatt switched Leo and Piper's powers. While Piper took to orbing easily, Leo struggled to control the power of molecular combustion.

Being the only one with an offensive power, Leo was forced to battle the Siren and found it difficult trying to target her, missing her twice. With much concentration and effort, Leo finally managed to hit the Siren and vanquish her.

When Mabel Stillman stole Piper's powers, she quickly learned to use it even though she was a low-level witch trying to use an upper-level witch's powers.

She was even able to channel it with one hand--something that Piper only mastered after several months. However, Mabel's aim was terrible; in contrast, by this time Piper almost never missed.

Another user would be the evil witch Tuatha. Although she did not possess this power naturally, she could access it through the use of her wand. With it she killed the innocent Betty. She was the first being to display this power.

Powers developed from Molecular Combustion
=== Molecular Acceleration ===

Molecular Acceleration is the powerful ability to to make molecules reverberate at a speed which causes them to become disordered, this causes an object to rapidly heat up. As a result of this heat, the power can cause objects to liquefy or burn.

Piper Halliwell received this ability in 2008 when she intended to blow up The Source of All Evil who had recently returned in the form of a golem, melting the road beneath him and slowing him down. She also exhibited the ability to focus this power onto a rope, burning through the middle and causing it to split. Piper Halliwell with this power can access the power of Pyrokinesis.

Notes and Trivia

 * This power is also referred to as Blasting or Blowing up.
 * Piper does not have to be directly in front of an object to blow it up, she just has to see it. However, her hands must move in the target's direction. Leo pushed Piper away from blowing up Kyra and her hands missed the target, blowing up a picture instead.
 * However, as she became stronger, Piper has shown in some cases that she doesn't have to directly see an object to blow it up, she just have know exactly were the object is. Piper blew up a vase without directly looking at it, until it had already exploded. Piper also blew up an incoming fireball without directly looking at it, because her eyes were looking downward at the spell.
 * In later seasons, Piper's power created more fire than in the earlier seasons. This was likely due to her growth in power.
 * Piper is the only one in the show with this power.
 * This is the most powerful power of the Charmed Ones, because they don't always have to say a spell in order to vanquish a demon or warlock.
 * Piper can freeze and blow up something simultaneously. The Source, when in possession of Piper's powers, was also seen to do this.
 * This is the last power used in the series to vanquish a demon: Piper blows up both Future Dumain and Past Dumain with this power, vanquishing both in one hit each and taking out Past Dumain as he tried to shimmer away.
 * Athough Piper needs to use her hands to use this power, her heightened emotional state in during the full moon allowed her to use this power without any hand gestures.
 * In the show, Piper uses this power much more often than her Immobilization power, yet in the comics, she uses her other powers more.
 * During the run of the show Piper used this power 242 times.