In Hangman, the computer chooses a random word (here, a Pokémon name) and reveals one dash for each letter in the name. The player guesses letters one after another; if the letter is somewhere in the name, it will be revealed everywhere it occurs, while if it's not, part of a picture is drawn. The player wins if they successfully reveal the entire name, but loses if the picture is completed.
Normally, the picture shows a stick figure being hanged, but this version is slightly less morbid: it has a Pikachu who will gradually charge a Thundershock. You'll know you're about to lose when it says "Pi" and "Ka"; you get a shock on the "CHUUU!" Depending on the difficulty setting you pick, the number of bad guesses it takes Pikachu to charge up changes.
The game has a scoring system, where you gain points for each Pokémon name you successfully guess, based on the estimated difficulty of guessing that name (which in turn is based on the difficulty setting, the frequency of each unique letter occuring in the name and the length of it). If you fail to guess a name, your score is reset to zero, but the game keeps track of your personal best score.
To guess, either click a letter or simply press the corresponding letter on your keyboard. In this game, to avoid having to input unique special characters, Nidoran male is Nidoranm, Nidoran female is Nidoranf, and Flabébé is Flabebe. Other non-letter characters are coded as _ (click "(other)" to guess that, or simply type _ on your keyboard).
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