For guarding other animals, a single older llama is generally
best. They will bond with their charges. If there is more
then 1 llama, they tend to bond with each other rather then
their charges.
Llamas work good as guards are they are real curious.
They see or hear something, they head to investigate.
They'll stick their faces right down to whatever it is and
that's pretty intimidating. Doesn't work well when they
are investigating rattle snakes, skunks or mountain lions.
A single llama can't take on more then 1 coyote at a time.
Multiple coyotes will come in from different directions and
start ripping them up.
That being said, I watched my 3 female llamas take on 6 wild
dogs at once. Wild dogs were coming over the back gate 1
at a time. As soon as each 1 hit the ground, the llamas
started in on it. They didn't kill all of them but the
rest of the dogs headed back out of the pasture real fast.