This Battlefront-style game isn't half bad.
Typical gameplay involves your side starting on one side of a battlefield, with the enemy on the other. You choose a class. Warriors tank through enemies and slaughter weaker classes when they are in melee range. Archers snipe foes at a distance. Scouts assassinate enemies, doing their best to kill single targets using stealth (yes, they can turn invisible). Mages support other classes using ranged attacks against groups of enemies, healing, and shielding from any/all projectiles. You use your character to capture and hold strategic points around the map. Your AI allies do what they can to aid you (fighting, and mages will heal you if you approach them). Your enemies will throw all they've got at you (try not to get swarmed). Your character is a typical soldier- you are not unique, and your health is equal to every other character, AI or not (depending on your class).
While you are fighting, you may be allowed to respawn as a hero of the LOTR world. If you wanted to annihilate hordes of enemies as a destructive powerhouse, here's your chance. Depending on the map, you could play as anyone from Frodo to Sauron himself. These heroes are useful in the extreme- don't waste them. Mage-type heroes are a little imbalanced, to tell the truth. They can heal themselves at a touch of a button, but it won't ruin the match for either side. Skirmish and multiplayer modes include Hero-only battles on some maps, which are an absolute blast to play.
Conquest can be fun, but it can also be unfair at times. If two warriors (AI or player) decide to team up on any single character, that character better think quickly. If several archers or mages gather, they could mow down almost all challengers before they even get a chance to attack. Scouts can instantly kill any single character with one stealthy move. Knockdown is the worst part of the game; if you are knocked down, pray that you'll get the chance to get back up. Every class has at least one attack that causes knockdown, so be careful.
Overall, LOTR Conquest is well worth its price of about 20$. You'll have fun on your own, or have a LOT of fun playing against other people.