While your character is putting away their weapon to talk to the NPC, rapidly press A to get unlimited money and EXP. Successfully complete any side quest that does not activate a cutscene when receiving your reward (for example, the 'South-Song' Gerralt's Corpse side quest or any 'Find And Deliver' side quest), then save the game. Have a saved game file from Dragon Age: Origins to unlock the Blood Dragon armor.