Lol. Didn't really think that one through, huh.
On the contrary, you obviously haven't thought it through. By even asking the question "Who created the wolf? Is God's creation cruel to other creatures God created?" it appears that you don't even realize that the way the world is now is NOT the way it was in the very beginning. This is a fallen world.
In the Garden of Eden, before sin came into the world, there was no flesh-eating, or bloodthirsty predators, or killing or anything like that. It was paradise, it was GOD's ideal, which was peace and harmony among all creation.
Even the animals did not eat eachother in the beginning, read Genesis 1:30! So you are either unaware of what the bible says... or SO guided by your belly and desire for flesh that you choose to ignore what the bible clearly says about God's ideal, which we can see in the beginning, and in the future restored world.
Speaking of wolves... this passage below is God's perfect will. You can choose to either honor it or go against it. For now anyway.... because according to the bible, this IS the future:
The wolf will live with the lamb,
and the leopard will lie down with the goat.
The calf, the young lion, and the fatling will be together,
and a child will lead them.
The cow and the bear will graze,
their young ones will lie down together,
and the lion will eat straw like the ox.
An infant will play beside the cobra’s pit,
and a toddler will put his hand into a snake’s den.
None will harm or destroy another
on My entire holy mountain,
for the land will be as full
of the knowledge of the Lord
as the sea is filled with water.
Isaiah 11:6-9