Straightforward Detonator with good timing flexibility.

S

+Unique Vis mechanics allows players to "save" damage towards nova turns, allowing for greater targeting/timing flexibility

+Diagonal attack during augmented state is strong for coverage and general damage

+Competes for highest ATK stat among Water units

-Provides no special value outside of Burst turns with Augment

-Heavily reliant on whale converters (Barton, Ruby, Bethlehem, etc.) to maximize damage output; the generic preemptive converters struggle to set him up for success

You want raw damage? Here's raw damage.

The closest comparison to Regal is the Forest element's Areia. Regal lacks Areia's overpowered equipment and his Chain Damage+Normal Damage buff is worse than Areia's flat ATK buff, but he offers better timing flexibility (including possibly lower effective CD when stockpiling Vis) and an added diagonal attack.

Overall, Regal is just a tad weaker than Areia, but that's still a great place to be. He's your best choice if you lack any of the truly overpowered water Detonators, and he's more than capable of clearing the game with just a little bit of set-up.