This came up playing with a different group than before. The Watchtower location ability says that you may summon and defeat a random monster instead of the usual check to acquire a boon. So should you decide which way you're going to try to acquire the boon before you get the random monster, or can you see what you would have to defeat first?
Thanks.
You must decide to fight the monster before you get to see what it is. Your choices are:
1. Do the check to acquire the boon
2. Summon and defeat a random monster
The power is not worded that you draw a random monster and then decide, it makes you choose between those two options. That means the choice comes before seeing the random monster (and if you decide to do the normal check to acquire, you'll never get to know what monster you would have fought).