Aside from all the dragons, I'd go for Deepcoil Worm. It was my first expensive card, and it's just such an iconic and beautiful card for the game. Really suited it well, always gives me a lot of nostalgia. Northstar and Cluster Explosion do a lot for me, too.
I'll just go through the most important things with this deck. If you need more information feel free to ask.
T1
Glacier Shell is missing. Building protects are quite important to keep your powerwells and orbs alive, which are the most important objectives in the game.
I would also recommend playing either Lightblade (purple) or Glyph of Frost in T1. They will help you in certain scenarios and provide alot more safety in many scenarios in the early to mid game
T2
Mountain Rowdy out: Slow meelee units are quite weak, because you can kite them
Phalanx out: Same problem as with mountain Rowdy, they are only useful in a shadow frost deck in combination with Nasty (Lightblade is also cool in combination with their Payback ability, but this is hard to execute)
Kobold Trick is missing as a second building protect here to provide safety against any kind of siege attacks
I also prefer Skyelftempler over Gravitiy Surge, but that's personal preference
T3
Northland Drake has horrible stats for 240 power and is only somewhat useful against a few decks that lack a proper anti air counter
Timeless One is missing here, one of the strongest T3 cards overall and has an amazing synergy with north star
Shield Building + Ashebone is strong, when you're going for a shadow splash in T3, otherwise amii ritual is also an option (especially in 2v2s)
Curse Well is also an option, but I despise this card, because it's completely broken
I used to play pure fire but i decided to drop out one nature orb in the middle it helps you specially with tier 2 stuff and if you are going BG regrowth or ray og light of light is a must beside you can always make a use of grimvine and one breeding grounds for less cost on summoning
Casperate liked a post in a topic by MrXLink in which card gives you the most nostalgia?