I suggest its better to stop barbaro at 3* . Its enough to get the job done. Start pumping Leoric by buying resetting his 3 x heroic = 60 diamond. 1 day you can
get 5-6 ss depend on luck , its faster than spamming guild points for barbaro. Instead of barbaro start spamming guild points in blake ss. By the time u reach a high level
in arena you should be able to have 5 star leoric and a decent star blake. Barbaro still decent at my level but when you are fighting 5 star leoric and 4 star blake you will
realize you should have start farming leoric and blake ss instead of wasting ss in barbaro 

hehe...  but this 15 heroes arena come too fast... should open lvl90 then slowly introduce 15 heroes... i think they leap a few versions.... heroes like lucia, mirana and dp is not even out but they started 15 heroes arena...

u forgot vip11 for mysterious box..

GG midnight got new patch

What to prepare? If they opened then u only can prepare ma.

My suggestion 

Team 1
Leo Jugo Bomo Gabriel Noire (Standard combo)

Team 2
Barbaro Vega Medusa Lumina Gyzmo (hard tanker with physical aoe nuke)

Team 3
Vincent Naomi Hyral Booster Eva/Drako/Buster/Int (int nuker)

test it 1st. vincent is suppotting vega.

My epic Arena Line Up :
Babaro, Tinker, Luna, THD, Hyral
Leo, Troll, Silencer, CM, Drow
Vincent, Jugger, Medusa, Sniper, Viper/Eva

All skilled , usually 30-49 ranked .
Still in training , have enough SS but still thinking open or not (Pandor)
Trying to get SS Magina (2 stars)

by the way naruko, last time which chinese server u link us? i wanna read more about heroes and strategies. thanks

i think pandor blake voo hyral booster can be a good team ... but i do not have 3 heroes there lol. if a high ranker can easily make pandor 5 * blake 5* and booster 5* too.

dream team
leo jugo bomo lumina noire
pandor blake voo booster hyral

but this team hard to achieve for me becoz my bomo is still 3 * hehe.