As many keys as you want, but one key per bot, if your friend uses your key while you are using it, you get booted off the game, well the bot anyway.
Very very low chance of being banned unless people report you for stupid things, like gather for 24 hours 7 days a week, teleport hacks, odd occasion where you run against a wall and it keeps jumping up and down, but that shouldnt be a problem as it will teleport (non hack) out, but if you keep doing it then people might report you.
Having said that, 4 bots on my server been using tele hacks to farm unspoiled nodes, some players reported them, been over 2 weeks, still alive and kicking, might be banned soon might not, depends on GM workload
Very very low chance of being banned unless people report you for stupid things, like gather for 24 hours 7 days a week, teleport hacks, odd occasion where you run against a wall and it keeps jumping up and down, but that shouldnt be a problem as it will teleport (non hack) out, but if you keep doing it then people might report you.
Having said that, 4 bots on my server been using tele hacks to farm unspoiled nodes, some players reported them, been over 2 weeks, still alive and kicking, might be banned soon might not, depends on GM workload