If Hidden Blade on the battlefield targets Jinx, and in reaction the player reveals Tideturner to switch with Jinx, does the spell fizzle or does Tideturner die?

Ruling: The Hidden Blade spell does not fizzle, but Jinx becomes an illegal target after switching locations with Tideturner. The spell resolves to no effect, and Tideturner survives.

Sequence:

• Hidden Blade targets Jinx on the battlefield
• Player reveals Tideturner in reaction and switches it with Jinx
• Jinx is now at a different location, making it an illegal target
• Hidden Blade resolves to no effect

Nuances:

• Tideturner is an exception to the normal hidden targeting restriction because its ability can never target units on the same battlefield where it was hidden (after errata)
• The hidden targeting restriction only applies when choosing targets, but targets must still be legal when the spell resolves
• If a target becomes illegal during resolution (like moving to another location), the spell resolves to no effect