Merfolk
A Modern deck, by Hunter Nance
2nd place at a tournament in Charlotte, North Carolina, United States on 2015-08-22

Maindeck:

Artifacts
4 Aether Vial

Creatures
4 Cursecatcher
4 Harbinger of the Tides
4 Lord of Atlantis (Not currently legal in Modern)
4 Master of the Pearl Trident
4 Master of Waves
3 Merrow Reejerey
4 Silvergill Adept

Enchantments
4 Spreading Seas

Instants
2 Dismember
2 Spell Pierce

Legendary Creatures
2 Kira, Great Glass-Spinner

Basic Lands
11 Island

Lands
2 Cavern of Souls
4 Mutavault

Legendary Lands
1 Minamo, School at Water's Edge
1 Oboro, Palace in the Clouds

Sideboard:
2 Relic of Progenitus
3 Spellskite
3 Tidebinder Mage
1 Dismember
2 Dispel
1 Hibernation
1 Spell Pierce
2 Unified Will