Warcraft III: Reign of Chaos

It has been nearly 15 years since the war between the Orcs and Humans ended, choose one of four races and join the renewed struggle for dominance.
An uneasy peace settled over the land while, for years, the drums of war were silent. Yet the kingdoms of men grew complacent in their victory--and slowly, the defeated orcish clans regrouped under the banner of a new visionary leader.

Now a darker shadow has fallen over the world, threatening to extinguish all life, all hope. The drums of war play upon the winds once again, rising urgently towards the inevitable hour when the skies will rain fire and the world will tremble before the coming of the Burning Legion. Armed with distinctive units, magical abilities and weapons of war, the Orcs, Humans, Undead, and Night Elves clash in their renewed struggle for dominance. The Day of Judgment has come.

The demo version of the game lets you try out both the single-player game mode and multiplayer on one map.