Froth Psynergy series

Froth (バブル, Bubble), Froth Sphere (バブルバルーン, Bubble Balloon), and Froth Spiral (バブルスパイラル, Bubble Spiral) are a series of Mercury Psynergies featured throughout the Golden Sun series. The Froth Series is believed to be the equivalent of the Thorn Psynergy series.

Basic Characteristics
Froth, Froth Sphere, and Froth Spiral are offensive, ranged Psynergies. The total damage inflicted is determined by comparing the caster's Mercury Power to the target's Mercury Resistance and using this number to modify the base power of the particular Psynergy in use.

Visually, each stage of the Froth series features a group of bubbles forming near the caster and striking the targets. Upon impact, the bubbles transform into a blue-colored spiral figure. The number of bubbles and spirals increases with each successive stage.

Availability
The Froth series is available to the Mercury version of the Seer class series, and the Medium class series. Thus, it is available to Mercury, Venus, and Jupiter Adepts. Mercury Adepts generally require large amounts of Venus Djinn to access the series. Non-Mercury Adepts require varying numbers of Mercury Djinn. Both classes learn Froth at Level 2, Froth Sphere at level 14, and Froth Spiral at Level 40.

Analysis
General: The Froth series is weaker than many endgame Mercury series, such as the Prism, Ice, and Cool series. However, it is usually available much earlier, when its power is useful. Despite its lower power, it is the strongest series available to both the Seer and the Medium, and is important for inflicting damage should either of those classes be in use. It should be noted that the series is the strongest Power-based Mercury series available to Venus Adepts, barring the use of Item-dependent classes in The Lost Age.

Enemy uses
Like many Psynergies available to Isaac and Felix's party, Froth is also used by enemies and monsters. A list of enemies capable of accessing the series follows.

Froth

 * Siren: Used 2 out of 8 times.
 * Fog
 * Sour

Froth Sphere

 * Sleet
 * Spritz
 * Hail
 * Dew
 * Steam
 * Hydros Statue: Used 53 out of 256 times.

Froth Spiral

 * Eddy
 * Balm
 * Serac