The game itself will be symbiotic and as competitive as the players choose to make it. If that happens, your task is completed, but the other player's economy will grow, as that adventurer brings your reward back home. The basic form of the multiplayer game is styled to be symbiotic and cooperative. Your heroes will use the other player's buildings if appropriate. At the same time there is nothing forcing you from being aggressive to your neighboring kingdoms if that is your style.
Players can put attack flags on each other's pieces, thereby trying to influence heroes to attack.
Again, when you place a flag you are leaving the reward there for ANY hero to claim. A hero with a low enough loyalty to his sovereign might just choose to attack his own kingdom's palace if the reward were great enough. Majesty will be at 800x600 resolution in 16-bit color. Yes, there is. It's a little over 45 megs and contains a level that will not be included in the final release version of the game.