ZZAZZ glitch
The ZZAZZ glitch is a glitch found in the Generation I games. It is encountered by using the Mew glitch that has a decimal number of 251, 252, 254 or 255. This makes the player encounter a glitch Trainer that in turn allows this glitch to occur.
One trait of this glitch is that it causes the opponent's Pokémon, usually a Charizard 'M, to have an extremely high amount HP. This is also a side-effect of using Super Glitch.
A side effect of ZZAZZ causes the trainer's name to become replaced with one that is much longer, composed mostly of A's and Z's. It also causes the Pokémon in the player's party to become glitchy as well, in addition to the player's sprite. Additionally, it makes three of the Pokémon's moves Explosion, and it will also trigger the move even when it is not selected in battle. Another known effect is that some or all of the player's Pokémon turn into Bulbasaur. A possible explanation to this is that the glitch overwrites certain variables and puts the hex value 99 to them, since the hex code equals to 'Z' as a character, Explosion as a move and Bulbasaur as a Pokémon.
The abnormalities listed above occur in Pokémon Red and Blue; the Yellow Version abnormalities which occur are different.
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