My oldest deck is [[Aesi, Tyrant of Gyre Strait]] which has turned into a bit of a monster since I added a few cards that happen to create a bunch of ways to make infinite Landfall combos. It could probably be even stronger if I took out some of the high-cost sea monsters to focus just on Landfall, but I like big sea monsters.
After that my [[Gishath, Sun's Avatar]] deck is pretty new, I just made it this year, but I already love it. Big dinos!