Adda

Adda is Merlin's former traveling companion who dies from drinking from the Holy Grail, shortly before his friend becomes an all-powerful sorcerer. He appears in "Nimue".

Before the Curse
The sun beats heavily down on some desert wastelands in what is presumably the fairytale land that was. Two men are soon seen running from over a hill of sand, clearly struggling to survive within this bleak terrain, and one of these men we see is a young Merlin, prior to his acquisition of sorcery. The other man, Adda, seems paranoid that they're being chased by something, but his traveling companion assures him not to worry, proceeding to spot a literal glimmer of hope on the horizon while the former collapses to the ground. He forces Adda to look at the distant sparkle, saying that there it is again, but Adda seems sure that it's a mirage and that there's no water there. Merlin, however, would rather find out for sure than lie there and die, beckoning his friend to come with him. The two of them are next seen approaching the source of the glimmer, shocked beyond belief to discover that, resting atop a stone, a silver, biblically-adorned cup awaits them. It contains much-needed water, and Adda is immediately convinced that it's a gift from the Gods. Merlin, on the other hand, doesn't believe that they're worth the Gods' notice, and so Adda comments that they could do worse before walking up to the cup by himself and taking hold with both hands, ready to lift it up and drink. However, his hands become frozen to the metal by magic and he begins to scream; it isn't long before the magical container reduces him to dust in a large array of gray smoke, to Merlin's revulsion. ("Nimue")