What does Reckless actually do though, and what's the timing? Is it timed like Enchantress and Ways, effectively being like Chameleon and saying "follow the card's instructions twice instead of once"? Or does it trigger after you have follow the instructions once?
The timing is "after following the instructions of a Reckless card due to playing it." And what it does then is, it has you follow the instructions again.
So, Reckless's "follow the instructions" works like Way of the Chameleon's "follow the instructions"?
So when you have Reckless Border Guard, Lantern affects the first iteration but not the second?
And when you use Elder to play a Reckless card, Elder affects the first iteration but not the second?
Tentatively yes to those.