Support it with Rain and give it Rain Dish for a boss support. Scald so every turn a physical attacker tries to mess with you risks fucking it over. Toxic Spikes to fuck over anyone who tries to outtank you and help out your team with Rapid Spin.
Last moveslot can be a lot of stuff. Sludgebomb Ice Beam or Dazzling Gleam to fuck over more pokemon directly, depending on what your team can't take. You can go Aqua Ring for even more stally though generally Tentacruel will be getting out once its done its job of chasing away a threat. Protect can give you an extra turn to regenerate HP with leftovers and rain dish. Or Knock off if you think your team would really like it.
>>18710139Definitely spin. Maybe knock off or aqua ring.