I finished Kena the other day - would highly recommend for £32 (though I expect it to go on the next sale as it's been out for a few months now). A really enjoyable game with a surprising difficulty spike. Goes from 0-100 at times, but lots of fun. Not sure I have it in me to go back and find all the collectibles, as the lack of any markers/mini map probably makes it a bit more time consuming than it needs to be. That said I only have about 20 rots to collect and maybe 15 other things, so not too much.
Started Guardians of the Galaxy, really good so far. They've done a great job with the cast of characters and the battle system is much more fun than I was expecting.