The ability that defines Syr Elenora's power works in all zones, not just the battlefield.

To determine the total cost of an opponent's spell that targets Syr Elenora, start with the mana cost or alternative cost that player is paying, add any cost increases (such as that of Syr Elenora's effect), then apply any cost reductions. The mana value of the spell remains unchanged, no matter what the total cost to cast it was.