RNSM

From BoardGameGeek:

'Your crew thought you'd planned the perfect crime, until a slip of the tongue put the cops on your tail! Outwit your criminal compatriots with clever wordplay to make sure you're not the one who gets caught.' In RNSM, players take turns adding letter cards to form new words from the available letters. With so many letters missing, you'll only need to provide the word if someone challenges. Play your cards right and you'll end up exonerated; make a risky bluff or a bad challenge and you'll almost certainly be apprehended! Every player receives a starting hand of letters, while one card from the deck is used to start the central row. On their turn, a player draws a new card and then adds one of their letters to the row. A player may instead challenge the previous player on their turn: the challenged player must provide a valid word that uses all of the letters in the central row in order, adding any additional letters as needed. If they can, they discard 2 cards; otherwise the challenging player discards 2. After each challenge, restart the row while leaving players' hands intact. The first player to discard all of their cards is the grand mastermind! For solo play, the player adds letters to the central row until they decide to end the game, at which time they must provide a valid word to score a point for each letter in the row. The more letters, the higher the score!