Andrew would section off a flat area (100x100 or so) about 5-10 or so dirt blocks deep. Then he would send a tp request to everyone on the server. If you wanted to join, you just accepted the tp and would be tp'd to the area. Then there would be a 2min (or so) period where you could build/dig, or whatever. After the grace period, he would say 'go' and pvp would be enabled. At the same time, all the blocks at a certain level would be changed. Every 5-60 sec he would change what the blocks were. Diamonds, Emeralds, Dirt, Coal, Stone, Etc.. This would go on for 10-15min or so or until there was only one player left. At any time you tp'd away, you were done. You could take what you wanted and not get back in. So... do you stay and try to get more at the risk of being killed. Or do you leave with what you have already collected. Some people would hunt others to collect their ores, others would hide away mining furiously. Be careful what you brought with you into the arena, because if you died, you lost it all.
Echest wasn't an option then. And... not sure about /back. I know you weren't supposed to set homes. (I never tried)
