Frost Psynergy series

Frost (チルド, Chilled), Tundra (チルドアース, Chilled Earth), and Glacier (チルドマウンテン, Chilled Mountain) are a series of Mercury attack Psynergy featured in Golden Sun and Golden Sun: The Lost Age. The first entry in the series, Frost, is also a necessary Utility Psynergy in both games, and can be granted to any Adept via the Frost Jewel.

Basic Description
Frost, Tundra, and Glacier are offensive, ranged Psynergies. The final amount of damage is determined by comparing the user's Mercury Power to the target's Mercury Resistance and using the difference to modify the base power of the particular Psynergy in use.

Visually, each stage of the series shows a wall of ice building up around the targets before shattering. The wall of ice becomes larger for each successive stage of the series.

Frost as a Utility Psynergy
In both Golden Sun and Golden Sun: The Lost Age, Frost is a common Utility Psynergy integral to solving many puzzles. Frost's most common application is to freeze small puddles of water into large ice pillars. These ice pillars are generally used as a mode of transportation; the player can jump onto and off of these pillars just like any stone pillar. It should be noted that in most situations, the only way to reverse the effect is to leave the room, and re-enter, which causes the pillars to return to puddles of water. While both available Mercury Adepts know Frost in their base class, the Frost Jewel allows any Adept to learn Frost.

Availability
The Frost series is unique to the Mariner class series, as well as the Water Seer class series, though only in Golden Sun and The Lost Age; in Dark Dawn, the Water Seer will have the Douse Psynergy series instead. Both classes are Mercury-based mono-elemental classes only available to Piers and Mia when they have no Djinn or only Mercury Djinn Set to them. Frost is learned at Level 1 for the Mariner, and at Level 2 for the Water Seer. Tundra is learned at Level 8 for the Mariner, and at Level 9 for the Water Seer. Both classes will learn Glacier at Level 24.

Analysis
General: The Frost series is a fairly weak series, learned early in an Adept's development. While useful early-to-mid-game, it quickly loses power when compared to other series. At the same time, it is efficient, as the player will generally not experience enemies in groups large than 3.

By Game
Golden Sun: Initially, for Mia, Frost is strictly inferior to Ice in battle, in that both are available when she joins and both cost 5 PP, though the latter does more damage. However, due to the large level requirement for Ice Missile, Glacier is probably going to be Mia's strongest multi-target Psynergy in the first game, which makes it quite useful.

Golden Sun: The Lost Age: In comparison to Mia, Piers has a larger pool of offensive Psynergies to to choose from overall. Glacier will be used interchangeably with Supercool of the Cool Psynergy series, as far as multi-target attacks go. Meanwhile, Piers also has access to Diamond Dust and Diamond Berg, powerful single-target elemental physical attacks. It still should be noted that Glacier is going to be the most powerful multi-target Psynergy until Piers learns Megacool at Level 48.