What is a Boxing League?
A relatively new concept in TCG/CCG circles, a Boxing League involves taking a box of your choice and building a 40 card deck -- It's that simple to begin (and even simpler thanks to resources like the YGOPRO virtual pack opener!). The league aspect comes in after the first game, when you can then take a number of packs (usually 6) from another set and opening those to supplement your existing deck, so as you and your friends continue to play against each other, the decks evolve beyond just a set, sealed casual deck.
Big pulls from Galactic Overlord! A buttload of Hieratics, a good pool of XYZs including Neo-Eyes -- Generic big dragon beatdown! Nitwit Outwit works like a treat here too.