The enemy used to send every formation straight at whichever of yours was nearest. Now it plans the whole army's attacks together, choosing the fights where it trades best.
Its cavalry looks for your archers and for the sides and backs of your formations, where attacks hit harder.
Enemy archers shoot the target they'll hurt most, and approach to shooting range without walking into your melee.
Enemy spearmen brace when your cavalry could reach them.
Its infantry advances as one line, and walks around rocks and buildings instead of getting stuck behind them.
It plays by exactly the same movement rules you do. In 200 simulated battles on different maps, the new enemy won 132 against the old one's tactics; the old enemy won 62 of 200 against itself.
GENERAL!