Going for a grindy fish build, getting a lot of value with +1/+1 counters
mainboard
no 1-drops, for more mid/late game grindiness, but could understand either having Jade Bearer or Kumena's Speaker in the main or side and maybe making some general deck changes
---Let's start with the 2 drops
-Winding Constrictor the reason for going black, but I wouldn't need to explain playing him (I hope). play 4
-Merfolk Mistbinder c'mon, you saw it coming, but not a 4 of since he doesn't give counters, but still really good, you should go 2-4
-Deeproot Elite he's far better than people think;especially with either the snake or the one below one the field. I'd play 2-4
-Metallic Mimic ever heard of a standard tribal deck without this guy? No? Good, me neither.. not much explaining needed here either. Play at least 3
-Merfolk Branchwalker worst case a 2/1, best case a 3/2 or better that triggers a ton of shit, I'd play 3
-Silvergill Adept so, he can be really awkward with only a snake or mimic on hand, but considering all the actual Merfolks in the deck, hopefully doesn't occur to often, so play 2-4
---- now the threes
-Jadelight Ranger the branchwalkers mother, for one g more, can become real big real fast, just the double green can become a problem, so I wouldn't go for 4
-Jungleborn Pioneer a creature with a fine body, that creates another one? He'll yeah (especially in draft) id say 2/3
-Kumena, Tyrant of Orazca usually overpowered cards with three good abilities are planeswalkers, I guess they messed up here.. he has all the right moves, in all the right places. No really, just imagine how long a board stall can continue with a +1/+1 counter for every creature (besides the snake) or even 2/3 a turn... that gets unbeatable.Play 3, perhaps 4 but beware the legend rules.
And the one fourdrop:
-Tempest Caller if the g kumena can't break the stall, or force through enough unblockable damage, this one will make sure of it for sure. You'll want no more than 2.
Noncreature spells:
Unsummon (might be replaced with Crashing Tide) for tempoish plays, getting rid of blockers etc.
-Spell Pierce to disrupt the opponent when you can, while not leaving much mana up.
-Hadana's Climb
so, i hope this one is spicy, it seems pretty hot, especially in this deck.it might become a 2/3 of or a 0 of , depends on performance.
-Deeproot Waters even with 6/8 non- merfolks , that leaves you with about a third of your deck merfolk, one with flash in the sideboard (more later). That seems perfect since you want many dudes for the tyrant. I'd run at least 2.
-Nissa, Steward of ElementsWow, just wow. Everything is perfect, a 3+ walker, with only good abilities, Can't say no to that. The +1 prepares your next moves, or the second ability that is really good in this low curve deck. And well, two flying lands win you quickly. 1-3
the sideboard
-Fatal Push could understand also / or playing Hour of Glory to hard remove bigger threats
-Kopala, Warden of Waves against removal heavy matchups
-Naturalize for many occasions
-Negate against control/ combo
-Nissa, Steward of Elements see above?!
-Sentinel Totem against gift and embalm businesses, maybe there's better options here?
-Swift Warden a Blossoming Defense with a 3/3 body, for three mana?! Well the lacking pump does hurt...
-Verdurous Gearhulk when played he can make a ton of value, but a little costly at 5
needs anti monored / aggro ideas
more description soon