[Palazzo]

1. You can get 99 by capturing 5 of every monster then going to the guy who runs the Monster Arena. Otherwise, the Monster Arena creations somtimes drop 1 (2 if they were overkilled) or you can bribe the Land Worms Inside Sin.

2. I looked at two FAQs and they say different things. One says you get 99 by catching 3 of every Wolf type monster then going to the guy who runs the Monster Arena. The other says you get 99 by creating the Cactuar King arena creation. To do this, it says:

"Capture at least one of each monster from the Thunder Plains. These
are: Aerouge, Buer, Melusine, Kusariqqu, Qactuar*, Gold Element, Larva, and
Iron Giant**.

*You will not encounter Qactuars until you've prayed to at least one of the glowing Qactuar stones.

**The Iron Giant only appears north of Rin's travel agency."

3. You can get 99 by catching 4 of every Bird type monster then going to the guy who runs the Monster Arena.