Wizkids Rules!

Which player decides the order for the blocking interaction?
Would a character that is knocked out stop or start triggering any abilities for the remaining block interactions if removing them would change the abilities requirement to being or not being fulfilled?

I'm not sure precisely what you're asking.

Here is an outline of sorts that I think should help you:
1) Declare attackers
-Any abilities that result from characters attacking happen now
2) Declare blockers (the defending player chooses every character that will block, and they choose which attackers those blockers will block)
-Any 'when blocking' abilities happen now
3) Use Action Dice or Global Abilities
4) Characters deal damage
-Abilities that happen from dealing or receiving damage happen now

Does that help?

-The Dice Masters Rules Team