Rogue Legacy is a pixel & retro style and rogue-like (in fact that's Castlevania-like, I think) action adventure game. The entire game features graphics & systems restoring the ancient ways and cartoon characters.
Vagrant Story (ベイグラントストーリー, 放浪冒险谭) is a great game work of Square Enix company in 2000. It comes from the same producer - Yasumi Matsuno with popular works Final Fantasy and Ogre Battle, and can be regarded as a perfect combination of RPG and SLG giants.
Vagante is a Rogue-Like indie small dungeon game inspired from Castlevania, Metroid, Dark Souls, and some other classic video game works. It has no complicated plot, only fairly subtle levels randomly generated by the program (including maps, props and its effects, equipment, traps, monsters, BOSS...), along with retro and pixel styles.
King Arthur's Gold (KAG for short) is a side-scrolling RTS type of small indie game based on the elements of Medieval Europe theme. It came up with retro & pixel style and unique, rare originality, and of course got inspiration primarily from one old video game King Arthur's World on SNES platform.
Crush the Castle is a physics and gravity based series of flash games developed by Armor Games - using the stone thrower (heavy catapult) to destroy the castles, which will make you think of the Angry Birds series (but with completely different style).
This is a nostalgic puzzle shooting game, even the background has the 60s, 70s' TV screen noise, with much good feeling.