Spent 700 keys over the week (including free keys) and got: 30 Kisame [Samehada Fusion Mode] frags, around 30-40 seal scrolls, 100 Anbu Kakashi frags, 180 Guy [Gate of Joy] frags, around 340 Purification Protection Runes and around 10 million coins.

Rest of the stuff don't really matter but the amount you get back is astounding. This event was crap when it first came out but they turned it into a gold mine.

Don't expect events like this one for a long while guys.