Haha, yea I understand what you mean. I also often start imagining people based on their avatar, and get surprised when I see what they really look like. xD
Yup, it was CPU on the computer! I played sometimes against friends, but not really competitive, just fun. We weren't aware of competitive leagues back then. On the computer the playable character was Yugi!
I used to play the Yu-Gi-Oh TCG, but now I barely remember the rules. I didn't know there was a ban list. So you play competitively? Good luck tomorrow morning!
AoH, It's not really a nickname either though. It was just a way of me saying happy birthday without only saying happy birthday. It sounded nice at the time. : P