For those who don't know, I'll give you the basics: Chimeratech Overdragon is summoned by fusing one Cyber Dragon and many other machine type monsters together. So if you play your cards right (no pun intended), you can get this thing's attack and defence points right into the 10,000 zone. Plus, depending on how many monsters you used for fusion summon, it will attack with that many fusion tributes. However, it is extremely rare to get, so you must be very lucky to get it in a booster pack.