The Swords of Ditto isn't perfect, but it's a fun little game in the spirit of the Zelda games that's definitely more fun to play co-op.
Upon pulling a magical sword from a grave, you're tasked with becoming stronger so you can take on the evil enchantress Mormo and bring peace back to the land.. at least for the next 100 years.
The game is procedurally generated and technically uses permadeath, but is set up in such a way that you're able to enjoy it without frustrations. Kids will enjoy the whimsical cartoon-like visuals, the literal "toys" that the characters attack with, and the cute kazoo-based soundtrack.
We set the recommended age a bit higher for this one (it's rated ESRB-10) because despite the cutesy visuals, some of the puzzles are not always clear and there's a bit of reading. Also, you pull swords out of children's graves. It's kind of morbid in that regard, but not much else.