Suggested by Destroyer An average Zombie is little more than a human with some slight durability. That’s not going to be enough against Green Arrow who can just spam a few good arrows. Arrow has dealt with many enemies in day who ranged from being immensely powerful to just being rather decent. He has more experience than any Zombie. Green Arrow wins.
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Most zombies are idiots compared to Oliver Queen, and will lose this battle. However, if it is the smarter zombies under play, then Oliver Queen has a good fight.
Definitely, GA should be able to out think most of these guys