Like others have said, using this with death cards would just be overwhelming. Run this in a deck with an entropy mark and death/aether towers, and you've got a nasty combination. If you are able to set up This+Graveyard, then your damage per quantum would get out of hand fast.
(As soon as you get 8
quantum, not meaning Turn 1 of the game)
Turn 1: Play this at the cost of 8
(0 damage)
Turn 2: Pay 5
and 1
(from your mark) (10 damage). Graveyard summons 2 2/2 skeletons
Turn 3: Pay 1
(14 damage) 2 skeletons generated
Turn 4: Pay 1
(18 damage) 2 skeletons generated
Turn 5: Pay 1
(22 damage) 2 skeletons generated
etc......
You just paid 16 quantum for 64 damage, and the numbers will only get more out of control over time. It gets worse if you can get a bone wall out (+4 a turn for the sparks dying) or if you manage to play more than one of these decaying particles.
Or a deck that runs aether/entropy could stall with phase shields while a few of these generate sparks that could be kept alive with chaos power would be pretty ridiculous.
It might actually be more balanced if you make it 1/10 or 1/20 so that at least it could fall victim to Fire Buckler/Permafrost Shield/Thorn Carpace/Turtle Shield.