Its Anafenza, Kin-Tree Spirit
For example, if you sort by alphabetical, your favorite decks will be sorted alphabetically, followed by the rest of the decks in your collection (also in alphabetical order, of course): Last Played will sort all your decks based on how recently the deck has been played, starting with the most recent and going backwards from there
His position and deck master were based on his dream of an all-penguin theme park, which Kaiba turned down
The fact that it stays a creature forever once you animate it is a huge deal
The Counter effect allows a character card to be trashed to add the specified value to the defending card's power, or an event to activate the effect as detailed on the card
Aggravated Assault plus certain mana-producing combos can also yield infinite combat steps