Water mage assassin.
The main protagonist was gifted in elemental manipulation. He was recruited at an young age to be trained in the water temple as a mage. However, when he returned to his village he found it in ruins. His house that he lived in with his mother was burned to the ground.
He saw an old looking chest in the rubble and found a fire-crested sword within. He set off on a journey to find out what had happened there.
I'm exploring what the character can do as in using the water elements to his advantage. I think it would be a pretty interesting concept to make him a silent killer because water seems harmless until you get swept into it's current.
A few more ideas for the splash.
1. Shows off his ability to create shards of ice from water.
2. Preparing ability to before an attack.
3. Rushing in for a kill.
4. Another ability of his is to enchant his sword with water to create a longer and sharper water blade.
I'm gravitating towards the 4th one. The idea of infusing weapons with magical powers seems really cool. What do you think?