x = 8, y = 8, rule = LifeHistory
3.C.C$.C3.C$C2.C.C$C2$6.2C$4.C2.C$2.C!
The goal is to find the smallest still-life (or constellation of them) that stabilizes all of the cells. IN this particular case, I believe the smallest stabilization is this, with 23 total cells:
x = 8, y = 9, rule = LifeHistory
2.AC.CA$.C.A.C$C2.C.C$CA2.A2$6.2C$3.AC2.C$2.C2.2A$2.2A!
Answers will be ranked by the cell count of the stabilized constellation. As a first challenge, try this:
x = 16, y = 10, rule = LifeHistory
C2$9.C$2.C$2.C2.C8.2C$3.C.C2.2C4.C$5.C$11.C$4.C$4.C!
Please don't use WLS, or JLS to find solutions.