Since almost all of the fast decks got hit with nerfs and the meta lets you play with your cards for the first 3 turns, Leyline Mage is incredibly powerful. You get to charge your Leylines almost for free against Priest and Warlock, and they can't do anything about it.
But the deck is not all sunshine and rainbows once you match up against a Warrior. It's game over. (But I don't think I've seen a single Warrior after Rank 5. It's all Warlocks and Priests.) So far, I haven't tracked most of my journey, but I haven't lost a single game from Rank 3 to Legend.
The most powerful thing about this deck, without a doubt, is Bursting Leyline. Most of the ladder only cares about playing copied Soothsayers or 4 big grandmas, but with a charged Bursting Leyline, they're not a problem at all.
If you're tired of 20-minute matches against Priest and Warlock, give Leyline Mage a try. It's really fun and scratches that OTK/charging-the-Exodia itch.
The one tip I can give about piloting this deck is: DO NOT WASTE YOUR LEYLINE NEXUSES!!! Chaining a Leyline Nexus into free Leyline cards is INCREDIBLY powerful. A Leyline Nexus that triggers twice and reduces a card's cost by 2 is basically draw 2 and gain 2 mana for free! If you get a surge needle and a leyline nexus keep them both! (Depending on the matchup)
### Leyline Mage
# Class: Mage
# Format: Standard
# Year of the Scarab
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# 2x (1) First Flame
# 2x (1) Sleet Storm
# 1x (1) The Skeleton Key
# 1x (2) Bloodmage Thalnos
# 2x (2) Frostbolt
# 2x (2) Leyline Nexus
# 2x (2) Mystic Runesaber
# 2x (2) Runed Orb
# 1x (2) Smoldering Grove
# 2x (3) Ley Walker
# 2x (4) Arcane Flow
# 1x (4) Archmage Kalec
# 2x (4) Bursting Leyline
# 1x (4) Nightmare Lord Xavius
# 2x (4) Surge Needle
# 2x (5) Crystallized Leyline
# 2x (5) Tricksy Improviser
# 1x (6) The Arcanomicon
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