Information adapted from the official forum.

The tiger pet was first available December 30th, 2009 from the release of the New Year Path: Ho the Tiger. The event has since ended and it is no longer possible to obtain the Tiger Pet at the moment. Entries on the official forum by the AM indicate that there will be a method to obtain them in the future.

The following are the instructions from the past event:
To obtain the pets, first accumulate at least 1000 points from the number guessing game (Port Coimbra channel 1) in order to gain the right to purchase the pet. After the 1000 point minimum requirement is met, win another round of the game in order to reach the dialog that allows for the purchase of a non trade-able baby pet box. Bring the pet box to the Pet Keeper in Gigante Dock to add the tiger pet to your family.

With 1000 points, it costs 400,000 fesos to purchase one of the tigers (your choice as to white, black, or ginger/golden). With 2000 points, it costs 250,000 fesos. With 3000 points, it costs 100,000 fesos.

The White Tiger can cast "White Bless" which lasts 20 minutes and can heal 1500 HP. The White Bless buff gives Immune +5, Movement Speed +10%, and Defense +10.

The Black Tiger can cast "Sharp Claw" which lasts 20 minutes and can heal 1000 HP. The Sharp Claw buff gives Pierce +5, Attack Speed +10%, and Critical +10. Each buff cast drains 1% food/energy.

The Ginger/Golden Tiger loots item drops every 2 seconds. The Ginger tiger consumes food at roughly 6% an hour, as opposed to the Poppet's 5%. Frankly, that's a great deal in maps that drop a lot of junk or for keeping a team without a healer alive during AFK.