Cost reduction on cards with X in text

By sappidus, in Rules questions & answers

Can you use Good Meal with Stand and Fight to, e.g., put a Northern Tracker into play for 2 resources?

Card text...

Good Meal: "Discard Good Meal to lower the cost of the next event you play this round that matches attached hero's sphere by 2."

Stand and Fight, cost X: "Choose an ally with a printed cost of X in any player's discard pile. Put that ally into play under your control."

Sounds legal to me

Yes it work.