The texts indicates we should remember that those who die in these tombs go to Merideth. Why would I remember that when this fact was not mentioned in the text until that point. It would be better to me for the text to indicate that those who die here have their souls sent to Merideth, and explain why. I would not make the assumption that the reader will have read all of the Aviontix before reading this sub, and this appears to be a major fact.
I had to do some searching to find out what Merideth is - the first occurance should be linked to improve readability, or even adding the phrase ("the Aviontix City of the Dead"), etc.
On a minor note - there are a few typos here - Gauntlet,greath,etc, and Larger has an extra capitalization.
On the plus side, it is interesting that an avian race would have tombs in the ground - it is contrary to ones expectations and provides a reason for what otherwise would be bizarre traps. Go to Comment
There are various comments about it being somewhat munchkin. This can be waved away by the simple expedient of saying 'almost' anything. The potion has a limited duration that necessitates multiple doses, the potion does not keep well, and the ingredients are hard to get - likely leaving a trail of crime that could be traced. I would expect any defenses against magic your game system provides to still be valid, so resistance rolls, saving throws and the like should still apply.
In short(?), a well detailed, well described potion that certainly fits the category of a wish-fulfillment item.