Here is the official thread for information about HDLC and OHDLC. You may be wondering what there they are called. Well here it is, HDLC is
Hacked
Down
Loadable
Content. Now moving onto what OHDLC is,
Overlapped
Hacked
Down
Loadable
Content.
<big>
Hacked DLC</big>
There have been six mass-distributed items of hacked downloadable content as of late:
ShinyBluePikmin: A color-negative version of the red Pikmin. It can enter a character's catalog - it buys and sells for 2 bells.
<div class='spoiler_toggle'>Spoiler: click to toggle</div><div class="spoiler" style="display:none;">
</div>
BlueLightSabreV1 and RedLightSabreV1: Both are versions of a golden axe, model and texture edited with the intention of resembling a lightsaber. These aren't able to be cataloged. Tom Nook can buy the BlueLightSabreV1 for 1,750,000 bells (though impossible to sell due to you not being able to hold the bells), and the RedLightSabreV1 for 250,000 bells. I don't have any pictures of the blue one but I do have one for the red, I also have a test one which was then posted on a site which will not be ]
<div class='spoiler_toggle'>Spoiler: click to toggle</div><div class="spoiler" style="display:none;"> </div>
DimentioMskHDLC: A hacked Version of the clown mask that has been edited to look like the Dimentio Mask from Paper Mario. It is, like the ShinyBluePikmin, able to be catalogued. You can buy the DimentioMskHDLC for 120 bells in the catalogue.
<div class='spoiler_toggle'>Spoiler: click to toggle</div><div class="spoiler" style="display:none;"></div>
TriPokeballHDLC: It is a hacked version of the triple shell but was edited to look like three pokeballs. As the ShinyBluePikmin, the TriPokeballHDLC is able to be catalogued. It costs 1024 bells in Tom Nook