These are Pok�mon with levels over 100. Ya, you heard me right. OVER 100. Here's the lowdown:
Why do these freaks of nature appear?
Well, when you fly back to the CIS from the Old Man demonstration, you know that the data stored for "What Pok�mon Appear Where" on the CIS is still the variable for your name (if you don't know why this happens, see Missingno). This means that the HEX Values for the encounters will be the values you gave to your name. Seeing as the game needs to bring up SOMETHING, it either brings up Missingno (or 'M) or it uses the HEX Values in your name variable. In this instance, the values used for letters 3, 5 and 7 are used as the Pok�mon Identifiers and letters 2, 4 and 6 used as Level Identifiers. For example: someone with the name "Pikachu" on their game would have the letters 'k' 'c' and 'u' used as the Pok�mon Identifiers, giving them Porygon, Charizard and Missingno on the HEX Value list.
How do you know which letter corresponds to which Pok�mon?
Use a HEX Value list for all Pok�mon in R/B(Y). A useful one is at TR Rose's site.
But what Level would they be at?
Figure it out for yourself! Heres how:
First take the number that is the equivalent to the letter. For example, 'a' is 1. Then add 127 if it is a capital (A) or 159 if it is normal (a). If you decide to use a symbol in your name here are the rest:
( = 154
) = 155
: = 156
; = 157
[ =158
] =159
Pk = 209
Mn = 210
? = 239
Pokedollar = 240
x (multiply sign) = 241
. = 242
That's pretty much everything on these cool Pok�mon, but remember that they wont stay that level forever. If you take them into battle and they gain Exp., they revert back to level 100. This also happens sometimes when you store them in the PC. If you want to get them back to Lvl 0, just Rare-Candy them up to 255. = )