The BLOB became a slip'n'slide, actually. Because it turns out that water rolls down hill, even when you think you have a pretty flat yard. (It almost took out my rose bushes. We literally had to stab it to get it to stop. It was ALIVE!)
Good news? Nobody cared.
We had a pool full of water balloons as an ice breaker, we turned on the sprinkler, and then I started randomly squirting my children and my friends' children with shaving cream.
They quickly picked up on the idea and went to town.
Cross one epic party off ye olde summer bucket list.