His hazards won't do much if we don't plan on switching. As soon as your last bonemerang returns to you smack him with a Bone Club. Then try to use your Bonemerang in close range, then your action depends on his status. If he's still spiking finish him off with another Bone Club as soon as the bone touches your hand, otherwise begin another Swords Dance to give yourself the advantage against whoever comes in.
Bone Club > Bonemerang > dependent
(If not fainted) Bone Club
(If fainted) Swords Dance
Fun fact: ASB Ho-oh, Groudon, Kyogre, Dialga, Palkia, Reshiram and Zekrom have more stars than Arceus. Mewtwo is one of the more average legends, having less stars than the fairies.