You know how on google dot com there is a text box and button to search websites on the internet? Can we please have a search box added to the duel/invade battle list so that we can search opponents by in-game name? Conquest Duel List and Festival Duel Champion List could also use the same search box.
Sometimes we meet opponents in guild battle and it would be nice if we could meet them again outside of guild battle, especially if they give good points in regular duel, conquest duel, festival duel, and war. And sometimes for mere infamy we know players in the game and would like to up their losses. An example would be zserg. We all know zserg wants to be chained, so it would be easier if we could search the battle lists for 'zserg' and have him appear there.
The second part of this suggestion is a search box on the Guild List page so that we can find guilds we remember from guild battle, or the infamous guilds we would like to find that we know by word of mouth. An example would be Cult of Padaxan. We all know Cult of Padaxan as the dev guild, but it would be nice to be able to enter 'Padaxan' or any other member of the guild, and bring up an entry on the Guild List page for Cult of Padaxan.
Note that I didn't suggest a cross-index of in-game names with forum names, so you couldn't search 'Elvis Presley' and bring up my in-game name. It would just be too difficult to match up forum accounts with in-game accounts, and other problems like volunteering information and right to privacy.