There are 4 ways the bounty will duel you, the following being:
Regular = 200TP. A regular duel, current ban list, just skill
Meta = 350TP. As it says, Meta will be allowed for the bounty, current ban list as well
Traditional = 450TP. The bounty can use banned cards, but can only use 1 of each
Unlimited = 600TP. Banned cards, but why it's different from Traditional is they can have 3 of each
Rules
Regular: no Kozmo, Monarchs, PePe, Exodia, Burn, Mill, and alt wins, if you lose, you cannot challenge the bounty again in this mode
Meta: no Exodia, Burn, Mill, and alt wins, if the Bounty Hunter loses to the Bounty, the Bounty Hunters have 1 try before they cannot face the bounty again in this mode
Traditional: no Kozmo, Monarchs, PePe, Exodia, Burn, Mill, and alt wins, Bounty Hunter has 2 tries before he cannot face the Bounty again in this mode
Unlimited: no Kozmo, Monarchs, PePe, Exodia, Burn, Mill, and alt wins, the Bounty Hunter is allowed to challenge the Bounty as many times as the bounty allows them
The bounty will choose how they want to duel