Submission: Till the Grave

The second text could just be:
Your prey burns 1 pool.
as above, and gain 1 pool.

I don't love it.

When i compare with a social charm, the chris version has 2 advantages: + 1 stealth, no bounce
2 issues which: you do not gain the edge (so a potential +1 pool or a vote) and this action costs 1 blood...
So as a bloodline card, it has to be strenghten:

Name: Till the Grave
Cardtype: Action
Cost: none
Discipline: Thanatosis
+1 stealth Action.
thn  The chosen methuselah burns 1 pool. If this methuselah controls the edge or if the edge is uncontrolled, you gain the edge.
THN  if you control the edge, you may burn it to make your prey loses 2 pools and you to gain 2 pools.

so comparing with a social charm:
At inferior loss of pools will be equivalent, and the potential gain of edge will be a little less than a regular bleed, but you got stealth
at superior, there is an aditionnal condition, pool loss is still in line with social at sup (2) and the gain is slightly more (2 instead of one but you lose the edge) and it is more powerful than an enticement (serpentis) for example.
So it allows some stratzgies with freak drives/bleed or till the grave inferior/till the grave superior.

i just regret that this card would not have the kind of trickster/jester/buffoon aspect related to the personnality of the voodoo figure of baron samedi.

i just regret that this card would not have the kind of trickster/jester/buffoon aspect related to the personality [of the Samedi]

Weeell, off the top of my head, Edge and transfer (better wording for untap/master phase counter movement?) denial would perhaps make things slightly more Trickster-like. As an example:

+1 stealth Action.
Your prey burns 1 pool. If they control the edge, it becomes uncontrolled.
as above, but gain 1 pool and put this card in play (you may only have one copy). The next time your prey transfers a counter between their minions and their pool during their untap or master phase, you may burn this card to cancel that transfer (no counters are lost).