Oceanic Blue Dragon Lair Actions?

[WarrentheHero]

In my campaign, there's an adult blue dragon the players are about to battle. Unlike most blue dragons, this one has made its home in the ruins of a mostly-sunken city, of which only the highest peaks of the tallest spires manage to rise above the waves.

As such, the Lair Actions present in the Monster Manual don't really work with this Lair. The third one works fine- lightning arcs across surfaces in the lair, but the first two don't work at all; there is no ceiling to collapse, and no sand to blind. Does anyone have any suggestions that could work in an open water environment, with combat primarily taking place on small circular platforms with narrow walkways between them?

[Kadesh]

Can you not just give it the Kraken's Lair Actions, which share electrical flavour? You can replace the last one with the Blue Dragon's Arc Attack if you wish.

[WarrentheHero]

That's a good idea, but the Kraken's lair actions are more geared to underwater combat, which isn't really the idea. But I hadn't really considered pillaging other creatures' lair actions.

[Vogie]

The Sea Dragon from Tome of Beasts has lair actions you can borrow:

• Summoning vortexes
• Wall of Coral that stings
• Localized Slow effects

[UnintensifiedFa]

I've got a few ideas.

• Summoning a wave. (Like the tsunami spell)
• Having platforms sink beneath the waves.
• Shooting platforms up so the creatures on them are open targets for the dragon. (But melee pcs can target the dragon)