The first time reading this card I was confused as to why you would use this end game, since you'd be dead before you regained the health to make the most of the max health. While I suppose it should have been obvious considering the fact that it is named 'Last Stand', and all the other Max HP spells also raise your HP, it confused me for a while so I suppose it could confuse a newer player who sees it in the bazaar.
Personally I like the image, I think it's pretty cool that the last stand is grabbing out towards the sun (even though it's a death card). Slightly ironic, but I think it works. I'm not sure everyone would agree, but I wouldn't mind some death/light friendship.
However, I'm not 100% sure about the name. Death is invietable, and I'm not sure it would be a death card that would try to cheat it. However if we changed either the name or the element I wouldn't get to rant on about how great the image is, (It's awesome) so keeping it seems the best solution.
I'm thinking this could work very well in a life/death with aflatoxin and bonds, since you'd lose health early game, then be able to regain it and have more Max HP for after you've saved yourself. (Makes full use of both parts of it, interesting card works in interesting deck)
In terms of balance, I would probably change the upgraded version back to 30 health, 40 seems like a lot to me. It would also make this cheaper, and if you really are about to die you don't want to worry about quanta.
Nice Card. Nice Image