Letter Head (2000)

From a review:

Actually many games (14) in the same box. Equipment is a set of cards each showing one letter and a point value (there are also wild cards).

You have a hand of up to 10 cards (you can draw as many as you like until you reach 10 - you start with 5). On your turn, you play a word to the table, with as many cards as you like face down. You announce the word, and everyone gets a chance to doubt you. You then show all the cards - if no one doubted you, you get the points for what you played (which could be QXZV, for a huge number of points). If someone did, you score if you were honest, with a bonus for each doubter. If you lied, the doubters get a bonus. You also get a bonus depending on your hand size and how many cards you played.