There's fundamentally no need to use any strategy. One reason is that Beastmen themselves are not adept at plotting, at least compared to the Human Race; Beastmen's talent in that area is truly lacking. Secondly, at the time, Beastmen didn't need to use such tactics. They merely relied on their superiority in strength, and theoretically speaking, if they were to just push forward directly, the Human Race wouldn't possibly be able to withstand their attack.
Therefore, since attacking was all it took to capture the enemies, for those relatively simple-minded Beastmen, there was no need to worry about anything else. In that situation, once an order was issued, it naturally led to all the Beastmen's large army launching an offensive toward the Human Race.
Facing that situation, no matter what the original thoughts of the Human Race's high levels were, in that circumstance, they could only put those extra thoughts aside.
"Kill!"
