5th Gen How to actually utilise Challenge Mode

I bought Black 2 about 6 years ago, played it through once - I believe on Challenge Mode - but hadn't played since and deleted my save in 2020.
Now I'm going to start a new playthrough and I'd hoped to use Challenge Mode, believing that as I'd previously defeated the game it would be unlocked for certain.
However I now see that if you delete your save, you lose your Keys (wish I'd known this previously...). Given from Gen IV onwards you can't save a new game when you have a previous save file, how exactly am I supposed to access Challenge Mode?

You need someone to send you a Challenge Key through Unova Link if you wish to start the game with Challenge Mode. Since NDS Internet Connection was disconnected a WHILE ago, you'll need to find a friend nearby.

shyguy-maru98 said:

You need someone to send you a Challenge Key through Unova Link if you wish to start the game with Challenge Mode. Since NDS Internet Connection was disconnected a WHILE ago, you'll need to find a friend nearby.

Click to expand...

So...even thought I already own Black 2 - which unlocks Challenge Mode upon completion - I'd effectively need to buy White 2, send the key over to it, reset Black 2 then send it back?

Seems completely irrational, so I believe you. I feel like Gen V is the first one where losing the wi-fi features kinda ruins it.

This feature is one of the most awful ones out there, and that's coming from someone who loves BW and Unova more than anything. It was very poorly-implemented. Needing another copy of the game to send that mode over to you (if they beat the game and unlocked it) is just silly, especially in the case of easy mode.. if you already beat the game then it's unlikely you'd need to make it any easier at that point. :x

I would like to add - in case anyone else has my initial query and finds this by searching - that once you unlock Easy / Challenge Mode after beating Iris, you can then activate it for the rest of your save. I realised this when I was using the Key thing for the Regis, makes Game Freak Nishino in particular a very tough opponent if you don't have a quick Fighting-type (my current team has Emboar, who has to use Superpower then switch).