Troops to bring: 600R / Max Losses: 441R
Camp 1 (40 Nomads, 40 Lance Riders) [Loss: 16R - 18R - 21R]
Camp 2 (40 Riding Amazonian Guards) [Loss: 18R - 19R - 20R]
Camp 3 Leader (60 Nomads, 40 Lance Riders, 60 Composite Bowmen) [Loss: 22R - 26R - 33R]
{Non-skilled Boris} 180R [ 56R - 63R - 74R]
When Boris arrive, send him to attack the middle leader, Camp 3, he'll kill all camps in his way.
Camp 4 (70 Nomads, 40 Lance Riders) [Loss: 24R - 27R - 31R]
Camp 5 (70 Nomads, 40 Riding Amazonian Guards) [Loss: 37R - 40R - 43R]
{Non-skilled Boris} 180R [61R - 71R - 74R]
Camp 6 Leader (70 Nomads, 20 Cataphracts) [Loss: 23R - 26R - 31R]
{Non-skilled Boris} 180R [23R - 26R - 31R]
Camp 7 Leader (90 Riding Amazonian Guards, 10 Uproarious Bulls)
Boris 180R [86R - 90R - 95R]
Camp 8 (60 Lance Riders) [Loss: 9R - 10R - 12R]
Camp 9 Leader (80 Lance Riders, 120 Composite Bowmen) [Loss: 21R - 30R - 45R]
-- Transfer {Boris} 180R up and attack Camp 7 in the north. He'll take out intercept camp in the progress.
Camp 10 Leader (90 Nomads, 90 Composite Bowmen) [Loss: 24R - 28R - 35R]
-- After Camp Leader 7 attack Camp Leader 8.
Boris 180R [24R - 28R - 35R]
Camp 9 (30 Riding Amazonian Guards, 40 Riding Bowmen) [Loss: 26R - 27R - 28R]
Camp 11 Leader (60 Nomads, 75 Riding Bowmen) [Loss: 40R - 42R - 47R]
-- After Boris returns, top him up with recruits from star menu and transfer him over to kill the southern leader.
{Non-skilled Boris} 180R [66R - 69R - 75R]
Done.
Just a rough guide for Boris I threw together, adjust as you wish.