kick is head or punch it
You can unlock the karts in any order so they are all here: Large Karts: Piranha Prowler - Win 50cc Special Cup Dragonetti - Win 150cc Lightning Cup Aero Glider - Win all gold medals in 150cc Cups
The exact reason is unknown, but there is a kart modeled after him (Piranha Prowler)and he was originally planned to be in the game (Beta Character Selection Screen icon of Petey found)
you have to do something
No, but the Piranha Prowler, a large kart, was modeled after him. Additionally, a beta character selection screen icon of him was found in the game's files.
u cant
win 10 tournaments coming in thirst
Complete all events in the game and achieve Level 50.
You can't unlock Petey Piranha in Mario Kart DS. It is myth character, and you could probably only obtain him if you sprite hacked and made some manual changes on the game. The four chanarcters which you can unlock on Mario Kart DS are Daisy, Dry Bones, Waluigi, and R.O.B. You can also obtain Shy Guy from hacks.
power rhymes with prowler
The cast of Prowler - 2012 includes: Rich Beckermeyer as Prowler
You can't get R.O.B or Petey Piranha on Mario Kart Wii, but you get Toadette by "Playing on all 32 courses in Time Trials mode or winning 1,000 Wi-Fi online matches." You don't have to unlock the Koopa Troopa. He's already there!
Win Mirror Star Cup. This also unlocks The Piranha Pipes Kart and King Boo.