I have defeated the lich king with all 9 classes. Here is the decklist so that you can do it as well! Hope this helps!
PS: Copy this: AAEBAaoIBNcPhBenzQKLzgIN7gHbA/4D9QT+BdAH8AenCJMJvxfjuwL2vQLHwQIA
and then create a deck. It will ask you if you'd like to automatically build it. Happy hunting!
Custom Shaman
Class: Shaman
Format: Wild
1x (1) Deadscale Knight
2x (1) Grimscale Oracle
2x (1) Murloc Tidecaller
1x (1) Sir Finley Mrrgglton
2x (2) Devolve
2x (2) Flametongue Totem
1x (2) Ice Fishing
2x (2) Murloc Tidehunter
1x (2) Vitality Totem
2x (3) Feral Spirit
2x (3) Hex
2x (3) Lightning Storm
2x (3) Murloc Warleader
2x (4) Call in the Finishers
2x (5) Bloodlust
2x (5) Volcano
2x (7) Everyfin is Awesome
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