Oberyn, back then he had the best gear of any of the lance cav and he was also just the best, he could also fight in melee and block, which was pretty rare back then. I always loved having lance duels with him, I remember that I bought a long awlpike to replace my heavy lance at some point, that thing only had 5 less lenght was amazingly fast and did tons of damage, I think it wasn't a day later that Oberyn used a long awlpike from horseback as well, I liked to believe this was because of me and it made me smile
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Also Chimp, definitely one of the best players back then. He walked around in some leather armour with a katana and a bow, did lots of damage with both but was still crazy fast. One of the original agi-stackers, I remember one time when he was last alive and fighting a horde of like 15 guys, he didn't win or anything but I was really impressed by how long he survived and his amazing blocking skills.