[Online Tournament for HoMM5 Players Who Like to Chat]

I don't understand much about playing as the Dark Elves, but I know that the basis of their strategy is hit-and-run. If anything, instead of wasting the army, you could attack with just the Rangers, slowly eliminating the Druids and other dangerous units. And only when you're confident, attack with the entire army. Here, you shouldn't blame the game, but yourself.