Age of Empires II: Definitive Edition

Easiest way to get this one is to do the Art of War naval challenge.

If you are playing through the campaigns, then the Suryavarman mission #4, Challenging a Thalassocracy, has a good opportunity to get this. You start with one demolition ship and can immediately train three more at once, from each of your docks. Send the four of them west and slightly south of your southernmost dock to Blue's docks. They have a starting demolition ship sitting there that you can destroy.

Didn't unlock for me on the first go and I suspect it's because it depends who blows who up. If their ship blows yours up before yours blow theirs up, then it doesn't count.

From the Main Menu:
Single Player > Campaigns > The Art of War > Naval Battle.

You will have to play the majority of the scenario.
Group up all your War Galley’s and Fire Ships to take out the first group of enemies.
Rearrange so the full health units are at the front for the next charge.

(Don’t worry so much about losing units here). Complete the second charge.

Halt.

Group together you Demolition Ships and squeeze them in line down the Southern side of the map along the riverbed.

Scan ahead East to see the third and final group of enemies. You will see a few Demolition Ships in the most South-Eastern corner.

Select you War Galley’s and Fire Ships. Send them into the middle of the two groups of enemy ships. Then immediately select your Demolition Ships to target the Enemy Demolition Ships. There will be a few explosions but the achievement should pop mid game or you may experience some delay.

The whole scenario should take 3-5 minutes.