I like this card, the thing it prevents it from being totally OP is its high cost (5
| 4
for a creature that serves as 1|1, 2|2 and 3|3 the first 3 turns isn't cost effective when compared to a zero cost 1|1 Photon|Ray of Light). At worst, we have a 1|1 creature with
"0: Growth, gain +1|+1" or something like that and the ability to sacrifice it in order to execute one last momentumed attack. At best, we have a creature with all said above plus fractal plus Shard of Patience plus Blessing plus a field full of Stellaries. But due to Stellri's high cost it is nearly impossible to fractal it with ease (a Crusader actually has the same cost and is more effective to fractal him because you can use endow in mass).
Because of all this analysis, I believe it is a pretty balanced and decent card. I kinda like it and +1 to DrakeX for making it.
* But I still have a few questions:
1) Is Fission an active or passive ability?
2) Is Collapse an active or passive ability?
3) Is Fission activated at the beginning or the end of each Stellari controller's turn? Are opponent's turns taken into account in Fission ability?