Dragon Cloud and Epicenter

Dragon Cloud (ぼくえんりゅう, Exploding Flame Dragon) and Epicenter (ぼくしんりゅう, Exploding God Dragon) are a pair of Mars Psynergies featured throughout the Golden Sun series. Among the single-target techniques, they are of a somewhat lesser popularity, but are considered among the Samurai series' best attacks.
Basic Characteristics
Dragon Cloud and Epicenter are offensive, single-target Psynergies. The final amount of damage is determined by comparing the user's Mars Power to the target's Mars Resistance and using the difference to modify the base power of the particular Psynergy in use.

Visually, both Psynergies feature a vaporous dragon, somewhat similar to the one conjured by Fume, that winds about itself as it heads towards its target. Ultimately, it pierces through its victim, creating a small explosion and throwing them back. However, Epicenter has a larger dragon than Dragon Cloud.
ExpandDamage calculation example |
Availability
Dragon Cloud and Epicenter are exclusive to the Samurai class series, available to Venus and Mars Adepts. Venus Adepts require large amounts of Jupiter Djinn and Mars Djinn, while Mars Adepts need Jupiter Djinn and Venus Djinn.
Dragon Cloud and Epicenter are learned at level 12. However, only Dragon Cloud is available at first: Many Psynergies are only available to the more advanced versions of a class, and Epicenter is no exception. What separates Dragon Cloud and Epicenter from most Psynergies is that Epicenter replaces Dragon Cloud. To access Epicenter, the Adept must be in the Ronin stage, which requires 5 Jupiter Djinn and 4 Djinn of their symbiotic element. Since Adepts in Golden Sun cannot have more than seven Djinn, the Ronin stage, and thus Epicenter, is unavailable.
Analysis

General: Dragon Cloud and Epicenter can be considered to be counterparts to the Flame User's Fume Psynergy series. As powerful single-target Psynergies, they can do large amounts of damage to enemies. However, the total amount of damage will be outpaced by Attack-based Psynergies late in the game. Despite this, they are still the strongest Mars-based techniques available to the Samurai, and are an effective counterpoint to Quick Strike. The main drawback is Epicenter's high PP cost, which can strain the Samurai's PP pool.