Blocking multiple creatures with multiple creatures
You can split the damage any way you like, as long as you follow the damage assignment order. The correct end result of the damage assignment is all that counts.


  510.1d [..] If it’s blocking two or more creatures, it assigns its combat damage to those creatures according to the damage assignment order announced for it. This may allow the blocking creature to divide its combat damage. However, it can’t assign combat damage to a creature that it’s blocking unless, when combat damage assignments are complete, each creature that precedes that blocked creature is assigned lethal damage.
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