This is an awesome io game where you play a piranha that eats small people to get bigger and runs away or attacks other piranhas played by other players. Depending on their size, you can eat smaller piranhas but the bigger ones can eat you. You get bigger with everything you eat and can go up a level. Once you have moved up a level you get smaller, but eventually, you can get bigger than you could in lower levels. Piranhio is a bit aggressive but if you can handle it you should have a lot of fun.
Use the left mouse key to move faster and the space bar key to use power-ups that you have found.