The games
Four word games built around one idea: that a puzzle is more interesting when the board has depth. Letterkeep, Stackle, Crossblock and Clue Countdown are all playable right now!
Letterkeep
Every tile you clear reveals another one underneath. Letterkeep is a word game with depth — literally.
The Classic board is a 6×6 grid stacked six layers deep: 216 tiles in all. Tap letters on the top layer to spell a word, submit it to clear them, and each cleared tile exposes whatever was buried below. The double- and triple-letter squares are salted through the lower layers, so the points belong to whoever digs.
- 15 board shapes — pyramid, hourglasse, ring, bridge and more
- Four powerups: dynamite, wildcard, lightning and magnifier
- Play solo, against the computer, or pass-and-play
- Online multiplayer by room code
Stackle
Play freeEvery puzzle is a themed list, and its words are hidden in the stack.
Pick a topic — U.S. states, one-hit wonders, things in a toolbox — and the letters of every word on that list are buried across a 4×4 board five layers deep. Tap exposed tiles to build a word that fits the category; find a full word and all of its tiles lift out at once, exposing the letters hidden below and making other words accessible. Clear the whole list to win.
- 12 themed packs, 20 puzzles each — 240 in total
- Three difficulty modes: Easy colour-codes every tile by word; Hard colours nothing
Crossblock
Play freeA crossword, shattered — put it back together.
Each puzzle started as a themed crossword, but we broke it apart into coloured blocks of three to five lettered cells. Your job is to drag every piece back onto the empty grid until all the words read again. Because the pieces interlock, placing one correctly tells you something about its neighbours.
- 5 packs, 20 puzzles each — 100 in total
- Medium rotates the pieces; Hard mixes in decoy words that fit nowhere
- Themes from English monarchs to movies, geography and the natural world
- Light and dark themes, and your progress is saved per pack
Clue Countdown
Play freeSix clues. Fewer used, more earned.
There's a hidden answer, and the clues to it arrive one at a time. You score whatever is still hidden when you guess correctly — so waiting for certainty costs you the round. Guess early and be right, or watch your points drain away one clue at a time.
- 100 themed series, five linked puzzles each — 500 puzzles, free
- Series run from Ancient Egypt and the Cold War to Animated Classics
- You set how fast the clues arrive, or hit Surprise Me and take what comes
- Each answer is followed by a short explanation of what it actually was
- Upgrade for AI puzzles written on demand, on any topic you name
Also built into Studiorum as one of its nine classroom game modes.