Darkmoon Card: Crusade

Source
This card is made by combining the Ace through Eight of Blessings.

Grants a total of 120 Attack Power and/or 80 Spell Power after successful attacks and stays active as long as you keep landing successful blows on that opponent within the next 10 seconds.

This is a great trinket for increasing your dps on raid or instance boss encounters, however you will not see the full benefit on regular mobs.

This trinket is of significant use to any spell/melee Hybrid class (Enhancement Shamans, Protection Paladins, and Retribution Paladins). Other classes may find specific uses for it. For example, the card procs off twice for each tick of Scorch, and off of each missile from Arcane Missiles, so after five casts or two casts respectively, the card will be fully stacked.