A couple ideas, Will update if I get more.
Support-
Strength in numbers: Being in proximity to other players applies a 1% damage reduction and 1.5% firerate buff to everyone in proximity. (Caps out at 10 players)
Alleviate: Press a key to release a healing wave (similar to orb of Christmas) that heals everyone in the wave for 15HP. (30 sec CD)
DPS-
Fight: Taking damage from the boss ups your damage by 15% for 5 seconds. (10 sec CD)
Vengeance: Being in proxy to a player death ups damage by 22% for 7 seconds. (10 second CD)
Mobility-
Flight: Taking damage from the boss ups your mobility by 20% for 5 seconds. (15 sec CD)
Self Conservation: Being in proxy to a player death ups mobility by 30 for 7 seconds. (15 Second CD)
Support-
Strength in numbers: Being in proximity to other players applies a 1% damage reduction and 1.5% firerate buff to everyone in proximity. (Caps out at 10 players)
Alleviate: Press a key to release a healing wave (similar to orb of Christmas) that heals everyone in the wave for 15HP. (30 sec CD)
DPS-
Fight: Taking damage from the boss ups your damage by 15% for 5 seconds. (10 sec CD)
Vengeance: Being in proxy to a player death ups damage by 22% for 7 seconds. (10 second CD)
Mobility-
Flight: Taking damage from the boss ups your mobility by 20% for 5 seconds. (15 sec CD)
Self Conservation: Being in proxy to a player death ups mobility by 30 for 7 seconds. (15 Second CD)