The Avengers #185 [Newsstand]-Good (1.8 – 3) Origin of Quicksilver And Scarlet Witch

"The Yesterday Quest!" Part 1 of 3. Ever since their first appearance in Uncanny X-Men 4 many years ago, the origin of Quicksilver and the Scarlet Witch has been a mystery to both comic readers and the siblings alike. After Wanda and Pietro arrive in Transia with Django Maximoff, clues to the twins' birthplace and birth parents begin to emerge. Modred the Mystic, the Darkhold, Bova the cow-woman, the High Evolutionary's former citadel, and Wundagore Mountain are all pieces to the puzzle. And the truth seems to lie at the top of the mountain. But there's something else at the top of Wundagore Mountain. Something ancient, something evil.
(NOTES: Origin of Quicksilver and Scarlet Witch;
First meeting of Modred- possessed by Chthon, and Wanda, where she encounters the Darkhold;
Mark Gruenwald's participation in this three-part story was an indication of the storyline's importance to the continuity of the Marvel Universe).