The first few decks I looked at required 4 Mutavaults, and several of them require 4x True-Name Nemesis. I'd hardly call Merfolk 'cost efficient' though. I'm also trying to avoid Force of Will, etc but I know if I were to go to a tournament, that's exactly what I'd need. Besides, the goal is to hopefully finish up in 3 or 4 turns, so taking 2 damage turn 1 for a Magus won't be a terrible thing. Of course they also had 8 fetches, but that's not going to happen because they're too expensive.

Breeding Pool is because I have them and they were in the WOTC deck I saw. I won't do that because I like Standard too much. If I stayed out of Standard a year, I could afford a competitive Modern deck, and if I stayed out of Standard for three years, maybe I could afford a decent Legacy deck. I'd like to be able to do an Affinity deck that lets me win in 3 turns, but I can't even do that yet. I stayed out of Modern long enough, and I started out with a very budget deck, just what I had from Innistrad Block, 4x of each of the Guildpact commons, and then what I pulled from Modern Masters. Had I not even seen the blue/green deck from Wizards, I would have continued avoiding Legacy.

Since I'm familiar with how a High Tide deck works because I've watched it played enough, I figured I'd start with what I know. The deck I'm working on/modifying is similar to one that was a deck on last year (plugged into SCG's deck builder, the total at the lowest cost would be $23 since I had Ponder and Breeding Pool).

Mtg edh manaless dredge