Although Zach didn't want to force these people to fight for him, they didn't have any other choice. There was no time to waste since the servants were cutting down the trees very fast. The destruction of their natural habitat was bound to anger the beasts living within it someday.
Instead of waiting for the beasts to attack first, Zach felt that it was only right to tell these beasts that the island belonged to someone else now.
Zach had thought of everything there was to consider. He had not only equipped the people he brought with him, but also geared them up to the point that the beasts would barely be able to get past their skin even with their most pointless attacks. With the protection of the suits, they could easily wade deep into the center of the forest and exterminate any unwilling beasts no matter the kind of situation that might present itself to them in the future.
