Hel's Gamble
Legendary prophecy
A gamble with Hel, goddess of the underworld, could reveal hidden knowledge or bring you to the edge of death; she will welcome you soon.
"You will face a challenge
With extra health equal to 50x the highest tower dps when this prophecy was foretold. It will reduce your health to 1%, if it leaks.
Defeating the challenge grants a permanent +50% damage to Vex."
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Edit: the original version (100x max hit) penalizes slow towers, like hitman and dark forge.
Maybe it would be better to make the health bonus 50x the maximum tower dps (not currently*, but max over the whole game).
* Current tower dps was my first idea (before I wrote this post), but then players would unequip the good items to deflate their dps before equipping the prophesy.
Edit: reworded prophecy to match Andy's prophecy wording. Added flavor text.
