So as some of you may know, it is possible to hex edit a pokemon to give a Kalos pentagon to a pokegenned mon.
Well now there's a very easy way to tell... simply take your suspicious pokemon to the memory girl outside the Anitstar City Pokecenter and if she tells you ''This pokemon has a good memory, but it cannot remember", sorry to say, you've been traded a hack.
A list of things I know to be hacks that are going around at the moment Shiny HP Ground Caterpie Timid Shield Dust Shiny 6IV Drowzee Shiny 5IV Bonsly Shiny 5IV Deerling (all forms)
How can a poke with a Kalos pentagon be from Bank?
This was posted purely as a means of identifying the rampant 'pentagens' that have been flying around these boards.
Wouldn't it be obviously genned if it had a pentagon but the catch info doesn't mention any location within kalos?
No, because the hex edit changes the game's version, so whatever the location in Gen 5 was, would become a corresponding location in Gen 6 (whatever happens to have the same area ID, the structure of the files is very basic).