Time for an easy #19:

Widely regarded as one of the best JRPGs to grace the seventh gen by those who played it, on the most impopular console for japanese games.

Lost Odyssey?

Yup :)

Hint for the game #18: The protagonist, still believes that Santa Claus exist. And one of his teammates mocks him because of it.

Hint for #18: This interesting collaboration between two unlikely partners taught us not only that you don't want to make a question angry, but also an important lesson with a shocking plot twist around 85% of the way through.

#20: Uncharted 3: Drake's Deception (Naughty Dog, 2011) - PS3

The Uncharted series never disappoints. Much like U1 and U2, I also nearly beat this game in one sitting. The action is still top-notch, the set pieces are BREATH-TAKING (seriously, the airplane falling? DAT boat level? Goddamn), the game is ridiculously gorgeous, the characters are as charismatic as ever, the plot is entertaining... One notable improvement this game has over U2 is the melee combat, it's MUCH better! I can't even tell you why, it just feels more fun and fluid. For some reason, many people consider this game a disappointment. I... honestly don't understand that... it's virtually on the same level as U2 for me, but oh well.

Hint for #19: this is the second game on the series. Even though it's actually the sixth game on the timeline. Most people would say it's the fifth game though (including myself).

Final Fantasy VI?

No no. When I say timeline, I actually mean that, all those games share the same world/timeline. They're continuations of each other's plots.

So Zelda II then?