Word chain game
This game is a very well-known Japanese word game, which is also very easy to play. You have to be at least two persons to play it. One person starts out by saying a randomly chosen Japanese word. Now the other person has to produce a word that starts with the same syllable as the first word ended with. Then it is the next person's turn, etc. You must not say a word that has already been said. If someone, by accident, says a word that ends with "n", he has lost, and the game restarts.
Normally, in order to limit the number of words that can be used, there is a rule saying you must only pick words that describe a thing or a phenomena. Only nouns and personal/place names are allowed.
If someone ends a sentence with for instance "ki" it is ok to start the next sentence with "kyo", since it actually starts with "ki" too. But if someone ends with "ka" it is not legal to start with "a".
Example:
Words like "myou" (strange), "ashita" (tomorrow) might not be acceptable, since they are not "mono", things, or phenomena.
Filling in the gaps
This is a rather traditional game too. It might sound easy, but when you try it out, it really isn't. This is more a way to make riddles than it is actually a game. The riddles are made up by writing a riddle, or a strange description, and the reader a hint by specifying all syllables except the first and the last.
Example:
Mainichi densha ya basu de kaisha e iku hito... __ukin__ Hana no oto... __sha__ Sore wa genjitsu ni okotta koto dewa nai... __rii__
The answers are: "tsuukinsha" (pendler), "kushami" (sneeze) and "doriimu" (dream).
Explanation game
This game is intended as an exercise in describing things, phenomena and conditions whose Japanese names you have forgotten. So if you become a master of this game, it should be easier for you to partake in a real discussion some day!
The rules of the game are like this. You think of a word, it can be anything from a noun to a verb. But typically you will think of it as a noun ("kankoukyaku", "asatte", "ugoku koto"). Now to make it easier for the other person to guess the word, you start out by defining the "scope" of this word. Where is this thing found... or if it is not a thing, is it a phenomena, a condition etc. You might say "Daidokoro ni aru mono".
Then you describe, not as a riddle, but as precisely as you can, the word you are thinking of. Typically you will make only one sentence. One of the good things about this game is, that you don't have to worry about making this sentence a real spoken sentence with subject and a nice ending and so on. Typically you just end the sentence with "mono" (thing), "koto" (when..., the act of...), "tokoro/basho" (place), "hito" (person), "joutai" (condition, state) or another noun (fune, kuruma, hon, shorui, dougu).
Since you formulate your sentence (your question) as a statement, the person that tries to guess what you mean, should formulate her guess as a questions (just like in Jeopardy!!).
Example:
Q: kumo wa mushi o okeru tame no mono. A: "kumo no su" wa nan deshou? Q: Kuruma o tomete wa ikenai basho. A: "Chuusha kinshi" wa doko desho? Q: Kuni no ichiban daijina seijika. A: "Daitouryou" wa dare deshou? Q: Mimi no gomi o toru dougu. A: "Mimikaki" wa nan deshou?
When the other person guesses your word, you say "Atari!"
What kanji is this?
The objective of this game is to describe a kanji to the other person, by how the kanji looks. Sometimes easy, sometimes difficult, this game can help you remember how the kanji look, because you can remember the often funny stories you invented to describe them!
Example:
Q: Mukuchi na hito ga noru tokoro. (A place where people of few word rest/stand) A: 台 Dai (Katakana "MU" + "kuchi"... mukuchi) Q: Me mo hana mo naku, 10 ko kuchi ga aru! (It has no eyes nor a nose, but ten mouths!) A: 古い Furui (Kanji for "10" + "kuchi") Q: Yane no shita de minna ga suki na raamen wo itsu tabeyouka? A: 今 Ima (hint: the letter beneath the "yane" is a katakana "RA") Q: 4tu no kaigara. A: 買う Kau