how about 1 ID / 1 IP, can enter freely thana room 1 time every 2 hours, but downgrade drop rate from thana card... so every player have different room (privat room)
1 player, 1 room, 1 times / 2 hours....
just like on P*rfect W*rld...
have 1 privat room for 1 player / 1 party...
how lucky are you, so you can get that drop card...