Fruit is tossed up from the bottom of the board, each one carrying a word. Type the word and your blade cuts it in half. Bombs carry words too, so read before you commit.
Fruit arcs up from below the board, hangs for a moment and drops back down. Every piece carries a short word on a label. Start typing and the game locks onto the fruit that matches your letters, picking the one closest to falling off the screen when two words start the same way. Finish the word and the blade sweeps across it: two halves tumble away, juice splashes the board and the points pop up.
A fruit that falls off the bottom unsliced costs a life. You have three, shown as hearts in the bar above the board. Lose all three and the run is over.
From the second wave on, some of the things in the air are bombs. They carry words like everything else, and finishing one blows up the board and takes a life. If the letters you have typed only fit a bomb, its label turns red. That is your cue to press Backspace or Escape, which clears what you have typed, and go after a fruit instead. Bombs that fall away untouched cost you nothing and count as dodged.
Word Ninja rewards the habit that separates quick typists from accurate ones: reading a word fully before your fingers move. Short everyday words make up most of the fruit, so you build speed on the words you actually type, while the bombs punish guessing from the first two letters. Standard mode starts slowly and forgives wrong keys. Advanced throws longer words, more bombs, and clears your letters on a wrong key.
On Standard the wrong key is ignored and counted against your accuracy, so you can carry on with the same word. On Advanced a wrong key clears everything you have typed.
Press Backspace or Escape. Either one clears your letters straight away so you can start on another fruit.
Each slice that lands within about a second of the previous one adds to the chain. Longer words get a touch of extra time, and the bonus grows with the length of the chain.