While the game is balanced with a rock-paper-scissors system, certain units can be upgraded to the point where they're virtually unstoppable in large numbers. (Elven archers, we're looking at you.) But not to worry - special weapons like the evil side's Watcher in the Water, which bursts through the ground at a chosen location and lays waste to enemy armies, can destroy even the strongest armies and prevent players from sitting back and building up impenetrable defenses.
There's also a new naval combat element to the game, but unfortunately it's nothing we haven't seen in every RTS since Warcraft II a decade ago. The more interesting addition is the War of The Ring metagame, a turn-based Risk-style board game campaign to conquer all the territories of Middle-earth. Wherever two armies meet, you jump into RTS combat to determine the winner. It's a great way to expand a simple multiplayer match.