×You can set up the soldiers on the inside. This is all about finding the right positions. You want to kill two guards immediately when the doors open, without your soldiers immediately getting killed. Place them near each other so they can watch each others back and not get surrounded. Beethro can help distract guards if the soldiers survive long enough, although with the right placement that's not necessary.

×You can place a guard outside on the grass. If he starts near the guards he can distract them while the second soldiers makes a kill or two. Beethro will have to circle around the remaining guards until the outside one can make his way in, and you'll definitely have to distract the guards to help him kill them.