It looks like a type of fire magic don't know if it's actually fire though could just be a energy blast. It would be cool to see the warlock form energy shields from his hand, or have healing hands to help out his team. Technomancy would be cool i mean the warlock has a robot flying near him so maybe it plays a role. i also think it would be cool for the warlock to imbue his powers into the weapons causing them to have more powerful shots or melee swings. And maybe an electrical current from his hands wouldn't be so bad either. But hopefully Bungie can think up new things, i'd like to see something new.