Question. I had the Ori and the Blind Forest but is the Definitive Edition worth the $5?

Where is the discount?!

You probably know this, but it's 75% off because you have the original. It's not because there's a running offer now.
So take your time to think about it since it's not going up lol.

For 5$ I'd say yes if you liked the game and want to support the developer. Pay attention you can only purchase it once, the option to purchase it as a gift will not be available anymore after the first purchase.

It's a $5 DLC, that isn't currently on sale [just, unlike scammy publishers, it's configured not to screw over previous purchasers].

If you enjoy the game enough, a $5 DLC should be worth it.
Flip side, in theory the discount should continue to stack with any discounts the Definitive Edition gets, meaning there's no real reason not to wait for a sale (certainly with Summer Sale coming up).
Yet on the other side of things, these kinda of promos have a history of not lasting indefinitely, so definitely keep a close eye on it if you're waiting on purchasing.