Current archetypes featured in the Merfolk Strategy Guide:

Amulet Titan (March 2019)

Hardened Scales Affinity (February 2019)

Izzet Phoenix (January 2019)

Krark-Clan Ironworks (December 2018)

Dredge (November 2018)

Bant Spirits (October 2018)

Mardu Pyromancer (September 2018)

Jeskai Control (August 2018)

Eldrazi and Taxes (May 2018)

Hollow One Aggro (April 2018)

Humans (March 2018)

Counters Company (February 2018)

Eldrazi Tron (January 2018)

Titan-Shift (December 2017)

Gifts Storm (November 2017)

Grixis Death's Shadow (October 2017)

UW Control (September 2017)

Affinity (August 2017)

Burn (July 2017)

Tron: RG, BG, WG (June 2017)

Jund (May 2017)

Infect (April 2017)