I have trouble seeing how Bonemerang is the optimal coverage over Low Kick. Hypothetically it's capable of breaking Substitutes and Sashes and Sturdy, but in practice the Substitute/Sash/Sturdy users I can think of will force Alolawak out, won't switch in against it, and/or won't stay in against it. Or they just aren't OHKOed by Bonemerang in the first place. Feel free to remind me of anything I overlooked.
Ground coverage is more useful versus Heatran, but Heatran will need Earth Power to make it worth staying in against Marowak, and Shadow Bone + Low Kick will KO 252 HP / 0 Def sets regardless. Low Kick also picks up the OHKO on Tyranitar switch-ins (except in the case of Chople Berry) without investment. Hydreigon has a 31.3% chance to get one-shotted by Low Kick too, fwiw.
Ground coverage is theoretically useful versus Toxapex, but rather than fish for such a risky 2HKO on the switch against a Water-type I would rather just click Shadow Bone and freely pivot out to something that doesn't care. Really, Shadow Bone is such a killer app for a pivot like Alolawak -- rather than play riskily with niche coverage moves or worry about the opponent pivoting around into a check, it can just click Shadow Bone and switch to something that's naturally suited for the opponent at hand. Tyranitar is the biggest deterrent to doing this, which is why I think the ability to OHKO it on the switch is invaluable.
Ground coverage is more useful versus Heatran, but Heatran will need Earth Power to make it worth staying in against Marowak, and Shadow Bone + Low Kick will KO 252 HP / 0 Def sets regardless. Low Kick also picks up the OHKO on Tyranitar switch-ins (except in the case of Chople Berry) without investment. Hydreigon has a 31.3% chance to get one-shotted by Low Kick too, fwiw.
Ground coverage is theoretically useful versus Toxapex, but rather than fish for such a risky 2HKO on the switch against a Water-type I would rather just click Shadow Bone and freely pivot out to something that doesn't care. Really, Shadow Bone is such a killer app for a pivot like Alolawak -- rather than play riskily with niche coverage moves or worry about the opponent pivoting around into a check, it can just click Shadow Bone and switch to something that's naturally suited for the opponent at hand. Tyranitar is the biggest deterrent to doing this, which is why I think the ability to OHKO it on the switch is invaluable.