It's acthully very easy just make an evil scientest who experiments with eridium and kidnaps chilldren and only one escapes with siren powers after geting infused with eridium

Name:the boomzerker

Action skill:allows him to enter a mode called "boomlust" where he throws c4 and dynamite for 12 seconds

Skill tree 1: boom-king which specializes the action skill

Skill tree 2:the boom-buddy which focuses on supporting allies by flushing out enemies

Skill tree 3: boom-builder which focuses on modifiiying his explosives (making his dynamite and c4 cryo,corrosive etc.)

Lore:one of the calypsos old eridium-tier subscribers after leaving the bandit life behind the atlas corporation and the crimson raiders come to recruit him to fight the new threat taking on a modified version of his uncle salvador's nickname "the boomzerker" (yes he is related to the gunzerker)

Meet Timmy the Battle-Skag, his Action Skill is to summon 2 more skags that help you in battle.

phaserend - rend the area around you, causing a phasebleed debuff that deals damage over time that penetrates shields

alt element: radiation

phasebuild - construct a wall of pure phaseflame that bars all projectiles and deals damage to everything that enters the wall

alt element: explosive

phaseflight - spread angel wings and glide across the battlefield, slicing and dicing all in your path. doubles as a mobility tool!

alt element: cryo

Its super very cool (at least i think so)