Hi everybody! I got R2 today so i like to share my way of winning tier 7 with you guys.
GAT (L) Level 80 Gear 8
Vader Level 80 Gear 9
ST Level 72 Gear 8
TFP Level 72 Gear 8
Magmatrooper Level 72 Gear 8
I put my best mods on them (Some 5* health mods with speed secundaries)
Try going for the buff immunity with TFP. This will prevent Chewie from taunting, Leia/R2 from stealthing, Han from giving everybody a buff. Go for R2 but at the same time try killing off Han, Leia and Luke. I fractured R2 with Thrawn everytime fracture was available. When Han, Leia and Luke are down everything becomes easier.
Kill R2, then Ben, then Chewie. You can switch Chewie and Ben if you like.
Took me some tries and a good RNG but in the end i managed to do it in 9 tries!
Hope this will help you all!