The main combo in the deck revolves around playing discounted Libram of Wisdoms on Eydis Darkbane (usually generated by Lady Liadrin). The neat part is that the deck only features one 2-cost minion (Murgur Murgurgle) and two 3-costs Brann Bronzebeard and Eydis Darkbane. If played correctly Rally! is guaranteed to ressurect Eydis Darkbane and Murgur Murgurgle. This way the deck can generate immense lategame threats with the Murgurgle Prime, as well as output lots of damage with Eydis Darkbane up to 3 times.
Along with these win conditions, the deck also features the combo of Brann Bronzebeard + Galvadon the Last Kaleidosaur, which is usually doable around turn 8 or 9. To support these win-cons, a Libram package is also included in the deck, which synergizes strongly with both the quest, Lady Liadrin and Eydis Darkbane. Keep in mind when playing the deck, that most combo or OTK matchups specifically are very tough.
To ensure strong and reliable card draw, the Holy Spells in the deck (Hand of A'dal and Potion of Heroism) are carefully handpicked, to make drawing cards more consistent. This works by limiting the number of Holy Spells without card draw effects, so the Knight of Anointment is likely to give you the draw you need.
Note that Lynessa Sunsorrow is NOT included in the list, instead i have put in Taelan Fordring. I myself have tried both variants, and found that Lynessa Sunsorrow has more drawbacks than benefits. She is very likely to overdraw and/or fatigue you, and also clogs the hand, which makes Lady Liadrin worse. On this matter (or others) I will gladly recieve feedback on the deck!
Happy playing, and I hope you enjoy playing this versatile Libram Combo deck!