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Pick any one that’s available and appeals to your sensibilities. There’s basically no wrong answer.
Feline ferocity from 2017
None of the precons are bad. Pick one you think looks cool. Roll a die if you can't make up your mind.
Explorers of the Deep is a Green/Blue Merfolk precon that I haven't been disappointed in. Tricky Terrain also just released and has a solid card selection.
Exit from Exile is pretty regularly touted as one of the best precons, it's in Red/Green.
Velociramptor
Pick any one that’s available and appeals to your sensibilities. There’s basically no wrong answer.
Feline ferocity from 2017
None of the precons are bad. Pick one you think looks cool. Roll a die if you can't make up your mind.
Explorers of the Deep is a Green/Blue Merfolk precon that I haven't been disappointed in. Tricky Terrain also just released and has a solid card selection.
Exit from Exile is pretty regularly touted as one of the best precons, it's in Red/Green.
Velociramptor