No prep. No Morals, Win with Kill. Amazon Rain Forest. 1 km away and have to track eachother
To the death is a tough sell with folks like Wolverine - who are very hard (almost impossible) to kill in any permanent regard.
Black Panther with vibranium suit, on the heart shaped herb, and sporting his energy daggers would give Logan hell (maybe even take a majority) ... But not to the death.
Wolverine all the way under OP's stipulations.