This is a cypher puzzle based on pictures of plants. Each plant corresponds to one of the seven letters B, D, E, G, N, R and U. When the puzzle starts, the seven letters and their plant equivalents are jumbled randomly, so there is no single solution. You can enter guesses at three-letter words, and the game will show you which ones are correct.
There are seven herb designs which you'll need to distinguish between. Identifying these seven and keeping notes on which maps to which letter should make this puzzle easy to solve.