On the night before Jack left Thereath, the night after he became a Beastmaster, he had hatched the Therras Beast Egg. Peniel had explained that the tame skill was most effective when the targeted beast was in its infant form.
Taming an adult beast was the hardest. An Archer needed to use bait and cage to trap and capture a live beast that was certain to be hostile. The beast was then given pet food and the Tame Pet skill was used at regular intervals. During this time, the beast might become agitated enough to break out from the cage. Thus multiple cages and baits needed to be prepared. The process was repeated until the beast succumb.
Capturing a beast at its young age was easier, as they had the least ability to resist. The taming process was the same but took less time. This was what Fierce Flame did with her Savage Wind Wolf.