"Masterpiece" is a word thrown around a lot these days in regard to things that made a lasting or maybe-not-so-lasting impression on people, but I truly believe Okami deserves that title.

It's hard to summarise Okami in a way that paints just how great of a game it is (no pun intended).

It manages to provide a 50+ hour experience while giving the player new challenges and things to discover constantly, I still find and learn new things in the game many years later.
It's jam packed with things to do, including a really long story (You beat what you think might be the final boss and you're only 1/3 through the story) with a tongue-in-cheek script, optional arena-type battles to test your mettle, even collectibles like the Stray Beads and monster checklists.
There's even multiple fishing mini games, racing minigames and lots of other stuff, I easily put in over 100+ hours on my first playthrough.

Accompanying it is a beautiful, melodious soundtrack and unique sumi-e, watercolour-esque artstyle that stood the test of time.
The gist is that the game looks like a painting, and even the small things like the animations and side quests were painstakingly crafted with love and attention to detail.
And with the HD releases, it looks and feels better to play than ever.

There is just so many things that it does right with all its aspects it's given as a video game medium.

I'm really glad Okami is getting the love it deserves even long after Clover Studio dissipated.
It really is a game (and a literal piece of art) unlike any other.