This amazing little card is actually a common from the Labrinth of Nightmare set.  It's use is simple: to prevent Special Summoning.  Simply having this card on the field will prevent strategies like Devil Franken's deadly one-turn kill.  Additionally, if you didn't get this card out in time to prevent a Special Summon, you still have the option of discarding a card to destroy all monsters that were Special Summoned.  Note that both Ritual and Fusion monsters are always Special Summoned, so this card makes it impossible to use either!

 

Now, the difficult part about this card is how to use it and how to keep it alive.  Playing it in face-up attack mode means that it can be killed by anything with an attack strength of 200 or more; even Sealed Left Leg can kill Jougen.  It's Defense strength isn't much better, and even if it was, playing it face-down won't enable his ability.

 

The obvious answer is to play Jougen face-up and to use support cards to keep him alive.  Mirror Force, Waboku, Attack Nullification, and other cards like them will protect Jougen, but only for a single turn.  Jougen's initial statistics are so pathetically low that it would take a handful of cards to make him strong enough to withstand an attack.

 

The best way to keep Jougen alive is to attach a card called MA-29: "A Mind that Reflects as Water."  It is a common Magic card from Mythological Age, and it prevents a monster with less than 1300 attack from being destroyed either by battle or by targeted Monster effects.  Play Jougen face-up, play the Magic card on him, and stick it out for one turn.  Note that you will still take any excess damage that flows over Jougen while he is in attack position.  Next turn, flip him to defense position and you're set.

 

So, if you're having trouble with Special Summons, look no further than your buddy Jougen.