It's funny but characters don't act like other fixed elements although it looks like they might. Try this and use a log. Kill Merlin first, then, knock over the tower or, hit the bomb at the base. The princess is actually standing on a bomb barrel so if you hit the bomb, you will only kill the princess!
If you just knock over the tower, your barrel bombs will do strange things.... This is neat and I think I know just what to do with this illusion.
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