What is the word for intentionally incorrect spelling?

I think the most popular ones are "Nite" for night and "Lite" for light.

If the word does not exist, this is your opportunity to coin one, which could actually end up in dictionaries.

I would suggest something to the effect of "poetic spelling"

Wow, I can't believe there isn't already a word for this! The phenomenon's common enough that you'd think there would be a word in, at least, marketing/branding jargon. But I can't find anything like one.

"Allowed mutation" is fine, although such a common practice deserves something punchier. And it definitely isn't slang; there's such a thing as the "standard" spelling of slang terms, whereas this is non-standard spelling of both slang ("dogz"--at least, I *assume* this refers to "friends" and not "canines"; I'm not familiar with the expression "rogz for dogz") and non-slang ("phantasy") terms.

p.s. what the hell is a rog?!

interesting question! i'm sure there must be a word for it. i suppose it is a kind of poetic license, i.e. deviation accepted in context - though something like "phantasy" is not really deviation, it's invention. very interesting indeed!

let's create a term for it. i propose "allowed mutation"!

Slang? lol.