Why “OneMore”?

Rounds have random letters to work with, but ‘One More’ is available: a tile that can be any letter you like, to be used as many times as you like.

N I W F are given here. FIND and WIND use it a D; WINE and WIFE use an E.

https://store.steampowered.com/app/3806530/OneMore/

The extra letter can become any number of copies of a letter of your choice in each word. It's an 'E' in WINE and WIFE, and a 'D' in WIND.