The latest event on Howrse is called Ow's Memories. It's a brand new event that works like the "Memory" card game.
In the 11 days that have passed since the event started, I've gotten this far:
I just finished level 11 and got another Ow's Helios Ray. Yay! Now, I have two more to put on my horses, but I'm still missing one more for the next Ow's Helios Ray trophy.
Something that annoys me (and most other players, probably) is the fact that you only get 6 keys each day. The objectives can also offer a couple of keys sometimes, but it's still too few.
So I actually just spent 20 diamonds on two key packs, which've been offered this weekend, just so that I could continue playing and make some kind of progress. I'm a really impatient girl.
But anyway, now I'm off to start playing on level 12.