From UO Evolution
Warriors have the ability to tap their magical Mana to perform devastating maneuvers with their weapons that can have a variety of unusual side-effects. Each weapon type in the game has a primary and a secondary special move. Warriors who have reached Expert skill level in both a weapons skill and Tactics (70 or higher) may execute a weapon's primary special move. Once he or she has reached Master status in both a weapon skill and Tactics (90 or higher), the fighter may execute the secondary special move while wielding appropriate weapons. Each different type of weapon in the game has a different combination of primary and secondary special moves, making each weapon truly unique!
An icon on your Paperdoll will open a book that details each special move available based on your skill level and equipped weapon. Much like the icons in a Spellbook, these can be dragged from the book into the game window and double-clicked to activate the special move. The special moves can also be configured in macros for one-key activation. When activated, the special move icon highlights red, indicating the character is ready to perform the move. At the next opportunity, the special move is performed, and the icon returns to its un-highlighted state.
Special move mana cost can be decreased by having multiples of certain skills. With 200 to 299 combined skill points, the cost will decrease by 5 mana. Having 300 or more it will decrease by 10 mana.