Use hammer and anvil, only use a really thin anvil. I mean really thin, three men deep units of lugoae in the center. Use slingers only for their family members. ALWAYS bring uirodusios or, if possible, gaesatae, because often AI sends a fullstack without FM, so they rout pretty easily. My battle line usually looks like this: Bataroas, Botroas and rest of your heavies take the far flanks, in the center static shallow line of spearmen with uirodusios behind, and operating as hammer family and leuce epos. I destroyed sweboz before reaching MICs for brihentin or neitos, nor did i need them. Also, i didn't really use slingers much, at least not against the sweboz... Btw, casse do an even easier job against sweboz. And, it is usually much easier when dealing with AI that spams fullstacks to be on the defence. For example, go into their province, and stand on a bridge/river crossing, and wait for the slaughter.