I have found Murloc Shaman to be a cost-effective option that still does very well in Diamond rank. (https://imgur.com/a/XTnpOhM)
This is the full decklist, with just 1 legendary, and only commons and rares.
Murlocs
Class: Shaman
Format: Standard
Year of the Gryphon
2x (0) Lightning Bloom
2x (0) Murloc Tinyfin
2x (1) Murloc Tidecaller
2x (1) Spawnpool Forager
1x (2) Cagematch Custodian
2x (2) Crabrider
1x (2) Firemancer Flurgl
2x (2) Lushwater Murcenary
2x (2) Lushwater Scout
2x (2) Murloc Tidehunter
2x (2) South Coast Chieftain
2x (3) Coldlight Seer
2x (3) Nofin Can Stop Us
2x (3) Voracious Reader
2x (3) Whack-A-Gnoll Hammer
2x (4) Felfin Navigator
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To use this deck, copy it to your clipboard and create a new deck in Hearthstone
I would replace Firemancer Flurgl with a second Cagematch Custodian, Prize Vendor or Rockbiter Weapon, but I have not tested it out.
The Core Set provides you with 4 rare and 4 commons already, saving you 560 dust. The total cost, if you’re missing all the cards is 2800 dust, only 1200 dust if you replace Flurgl with a cheap card.
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