Reread comics 1 through 16 and came to a single significant concluion: I really want to know what the hell the Serpent and the Garden are.
For those who dont read the comics, after a failed attempt at radical ecoterrorism and one of his famous deaths, Ra's al Ghul orderred his subordinates in the League of Shadows to prepare "the Serpent", commenting <paraphrased> that if their dealings with the light do not pay off, then only "Eden" will suffice. "The Garden" was also mentioned though i take it to be synonomyous to Eden.
Ra's goal from the comic is clearly to revert the world to a state with nature as the dominant force on earth. He was using a diamond lense to make precise strikes from orbit to destroy developed cities around he world. Eden was known as the perfect, untouched garden of biblical mythology, created as the natural home for mankind so long that they remained within their limited means. So it makes sense that Ra's would use a codeworld with such connotations for his idea of the perfect world and the means to obtain it.
However, outside this "Eden" was allegedly a complete wasteland, this world where two of the first humans were forced to fend for themselves to even obtain scraps was the ultimate punishment for disobeying their god. Because of this it could easily be made into a global level threat, Ra's new Serpent creates a paradise, while everything around it is completely destroyed.
As for what this "Serpent" is i have one idea though it draws from a different mythology and a different game altogether. In Tomb Raider Underworld, Jormungandr was described as a metaphor for the tectonic plates encircling the Earth, with the idea that by activating them triggering massive tectonic activity which could activate numerous volcanoes, particularly those on the ring of fire, bring the earth into smoldering wasteland. locations away from plate edges and volcanoes would be spared from the majority of the destruction and could likely be further protected to maintain them as "Eden"
Because we dont actually get any information beyond a name from the comics, the Garden storyline could realistically be played out in any medium; Comic, Show or even the Game. If in the comic then it's an eventual continuation of the storyline, if in the game then it'd be a bit of a shame since we are obviously much more interested as a fandom in what we missed during the five year gap then the potential storyline we got in something most people here dont seem to even read. If in the show then it's no different then Claface's appearance, he was fully explained in the comics and actually carried on from this little plot element. We dont know anything and neither does the team meaning regular fans wouldnt lose out by the exposition required.
Anyway that's about it, if you have any ideas about what the Garden could be, feel free.