Vikings
[M,M,M,B,B,C,J,C,B,B,M,M,M]
[F,F,F,W,W,K,E,K,W,W,F,F,F]
Saxons

To make matters easier, let's convert these walls into numbers:
Round 0:
 M M M B B C  J  C  B B M M M
[8,8,8,6,6,10,15,10,6,6,8,8,8]
[5,5,5,8,8,10,20,10,8,8,5,5,5]
 F F F W W K  E  K  W W F F F

Round 1: Notice that 2 of the Saxons' warriors are adjacent to Knights, so they have a +1 damage bonus.
 M M M B B C J  C B B M M M
[7,7,7,4,3,8,14,8,3,4,7,7,7]
 | | | | | | || | | | | | |
[4,4,4,5,5,8,18,8,5,5,4,4,4]
 F F F W W K E  K W W F F F

Round 2:
 M M M B B C J  C B B M M M
[6,6,6,2,0,6,13,6,0,2,6,6,6]
 | | | | | | || | | | | | |
[3,3,3,2,2,6,16,6,2,2,3,3,3]
 F F F W W K E  K W W F F F

Round 3: Remember to collapse the arrays to account for dead warriors. Also, notice that the 2 outermost Fyrd are now attacking the diagonally adjacent viking.
   M M M B C J  C B M M M
  [4,5,5,0,4,12,4,0,5,5,4]
  /| | | | | || | | | | |
[2,2,2,1,0,4,14,4,0,1,2,2,2]
 F F F W W K E  K W W F F F

Round 4: Notice once again the saxon Warriors next to the Knights dealing 3 damage:
   M M M C J  C M M M
  [2,4,2,2,11,2,2,4,2]
  /| | | | || | | | |
[1,1,1,0,2,12,2,0,1,1,1]
 F F F W K E  K W F F F
Round 5:
 M M M C J  C M M M
[0,3,2,0,10,0,2,3,0]
 | | | | || | | | |
[1,0,0,0,10,0,0,0,1]
 F F F K E  K F F F

Round 6:
    M M J M M
   [3,2,9,2,3]
      | | |
     [1,8,1]
      F E F
Rounds 7, 8 and 9:
    M M J M M     M M J M M     M M J M M
   [3,1,8,1,3]   [3,1,7,1,3]   [3,1,8,1,3]
      | | |          |/           |/
     [0,6,0]         [4]           [0]
      F E F           E             E

Output: Viking victory.

V: [M,M,B,C,B,C,J,C,B,C,B,M,M]
S: [F,F,W,K,W,K,E,K,W,K,W,F,F]
O: Viking victory.
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V: [M,M,M,M,M,M,M,M,M,M]
S: [W,W,W,W,W,W,W,W,W,W]
O: Saxon victory.
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V: [B,C,M,B,C,M,M,C,B,M,C,B,M]
S:   [W,F,W,F,E,E,E,F,W,F,W]
O: Viking victory.
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V:         [B,B,B,J,B,B,B]
S: [W,W,W,W,K,K,K,E,K,K,K,W,W,W,W]
O: Saxon victory.
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V: [J]
S: [E]
O: Viking victory.
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V: [C,C,C,C,B,B,M,M,M,M,J,J,J,M,M,M,M,B,B,C,C,C,C]
S: [K,K,K,K,K,K,K,K,K,K,W,E,W,K,K,K,K,K,K,K,K,K,K]
O: Saxon victory.
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V: [M,M,S,C,B,J,B,C,S,M,M]
S: [F,K,P,W,K,E,K,W,P,K,F]
O: Saxon victory.
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V: [S,S,S,...,S]
S: [P,P,P,...,P]
O: UNDEFINED (since both priests and skalds deal no damage, you can output anything here.)
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