Knights of the Silver Hand

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The Knights of the Silver Hand is one of the coolest aspects of Warcraft. A paladin order, they debuted in Warcraft II, was destroyed in Warcraft III, and recently had a resurgence in World of Warcraft. What's interesting about the Knights though is how they came to be in-universe. In the first Warcraft, you had Clerics of Northshire, priests with powers to heal, become invisible, see far away, and one offensive spell called holy lance.

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In Warcraft II, clerics were replaced with paladins, an upgrade for knights that gave them the ability to cast spells similar to what the clerics had. Now, in the manual for the second game, it was explained that the clerics had suffered heavy losses during the First War (the first game), due to their lack of martial training and that two figures - Uther Lightbringer and Archbishop Alonsus Faol - came up with the idea to create an order that would meld the dual roles of warrior and cleric into one, thus the Knights of the Silver Hand was born. I like how Blizzard actually took the time to give an explanation for the clerics replacement in Warcraft II, it really does give the games more depth.

Edit: Did some picture swapping.