Guild Wars 2

It took till level 72 at least but this is a story mission underwater. As an Elementalist I have exactly 1 attack that works underwater and it’s on a 3 minute cool down. Theoretically I might be able to get through this if I alt-tab out every few minutes to read a book or something but given all the crap story missions pull out on land it’s entirely possible after seven hours or so I’ll hit a brick wall. Is this mission even possible?

Yes, it is possible to solo with an ele.
Just keep trying, or ask someone to help.

Fire 2, 3, 4, 5 ( single burst )
Water 2, 3, 4, 5 ( standard fare )
Air 4, 5
Earth 4, 5

Plus your 3 minute move.

Finished that mission only using Fire so it’s not really hard. Otherwise just stay in water, use 5, to drill through the enemy, use 3 to get back out, 2 to deal more damage and swap out to Air to use 5 and 4 to stall or Fire 2, 3, 4, 5 if it’s solidly on your NPC buddy. Water 5 is the strongest move we have, use it correctly and it will destroy whole groups. Especially useful in under water fractals and dungeons but it works fine here as well.

Honestly, Krait and Undead both sucks, especially under water but still possible.