This is the Touhou game I spent the most time with. It's fine enough single-player, but a vs. shooter like this is it's at its best when you're playing with a friend.

Each of the playable characters has their own distinct attacks and playstyle, sending over various obstacles to their opponent. I like how instead of a single bomb type, there are progressively more powerful spells you can use as you kill more enemies. Komachi in particular is so much fun to play as with the sheer amount of bullets in her spells. As usual, ZUN's soundtrack is great. Wind God Girl is one of my favorite tracks in the series. 2-player mode is a lot of fun and can be played locally or online via peer-to-peer connection.

The only issue is that controls get uncomfortable after awhile. There are control options, but you have to decide between no autofire or no unfocused movement when firing, neither of which are ideal.