Liquid Magic

Summary

The proverbial mother of water magic, liquid magic focuses on the creation, manipulation, and utilization of matter in a liquid state. While this includes water itself, unlike water magic, liquid magic influences all liquids encountered--or, as much as its respective mage can actually do. In most academic circles, liquid magic is considered the root mother, with things like water and blood magic being children that branch off of it. Smithing professions argue about things like molten metal manipulation being apart of the family, so the boundaries tend to move back and forth. The ubiquity of the art form means there's quite a lot of differing opinions about the matter.
As a whole, liquid mages are as desirable and useful as water mages, with the added benefit of whatever particular specialization they're involved with. It is noteworthy to detail that most liquid mages do specialize in handling certain liquids, as per those liquids properties. As above, those handling molten metals, but also ones handling various types of chemicals, blood, magma/lava, and even exotic materials such as pure mana. Certain training and awareness of said liquids is important to the survival of the mage, let alone effective utilization of it. Depending on their specialization, cross-over training may be more complicated than learning other forms of magic, or a fairly trivial affair.
Compared to the history of water mages, it can be more difficult picking out liquid mages. Typically, forging-related fields showcase them the most, followed by exotic professions around items like liquid mana or volcanic magma. Unfortunately, this has the effect of making them seem less worthwhile than just being pure water mages. That is, their flexibility with liquids in general is just not a great selling point. And so, for regions that don't particularly exploit their talents, many liquid mages end up being full time water mages for their careers.
This does, of course, surprise the ones who make the foolish mistake of only thinking they can affect water.

Effect

Liquid magic affects liquid-matter states. the particulars of the effects often rely on the given matter, whether it is simply moving it, causing floods, ejecting high-speed geysers, or other techniques.

Side/Secondary Effects

Liquid created, if any, is liquid remained; and so any mage will have to deal with the aftermath appropriately. For a great deal of liquids, this can be especially dangerous compared to water.

Manifestation

Flowing currents, floating bubbles, roaring tides, and all sorts of liquid in motion or at all typifies this magic. The specific liquid itself can have some secondary effects--magma would radiate heat, roiling and bubbling; acids would react with anything that they can, etc.

Source

Internal mana; supplemental sources, if any are present, can help tremendously with operational costs. It's worth noting that creating 'complex' matter, such as chemicals, is inordinately expensive to the point of being practically unfeasible. Handling them, however, is trivial by comparison.