Loved this event but
The "get 15 level 3 upgrades" thing is pretty ridiculous when people keep surrendering before I can get 35 krakens. I have 5 so far after 10 games, and 2 were from the same game. I actually find myself trying to rally the enemy team to last a couple more minutes.
Not to mention the fact that it encourages players to only go down one upgrade path, because wasting 5/10 krakens when it's already hard enough to get 35 makes the icon even harder. So we've got people making suboptimal choices for an achievement.
I loved the event, but this part of it is something riot should learn from for the next one.