I don't think anything above 78 (or special-case 74) is really a "bad period". Sphenocorona's H-to-domino can supply those sparks in a true-period way.
Unfortunately Sphenocorona's H-to-domino doesn't work in this context:
Code: Select all
x = 228, y = 109, rule = LifeHistory
30.2A$30.A.A$32.A4.2A$28.4A.2A2.A2.A$28.A2.A.A.A.A.2A$30.BABABA.A$31.
B2ABA.A$32.2B.BA$31.3B$22.2A6.4B$23.A6.B2A3B$23.A.AB3.A2BA2B$24.2AB.
10B7.A$26.7BA5B6.3A$26.7B2A5B8.A$26.6BA8B6.A.A$28.8B2.4B5.A.AB$28.6B
5.4B5.A3B$27.9B4.4B6.4B$26.4B4.2A5.4B5.6B$25.4B5.A7.4B4.7B$24.4B7.3A
5.4B2.8B.4B.B$23.4B10.A6.17B.B2A$22.4B19.18B2A$21.4B20.16B.2B$20.4B
21.6BA9B$19.4B22.5B3A7B$18.4B21.2AB.3BABA6B$17.4B21.A.AB2.11B$16.4B
22.A5.10B$3.2A10.4B22.2A5.BA8B107.2A$4.A9.4B29.11B88.2A.A.2A11.B2AB$
2.A10.BA2B31.10B87.A2.2A.A2.A.2A.A4.3B$2.5A5.3AB5.2A25.8B.B2A.A82.A.A
4.A.2A.A.2A5.B.B$7.A4.4B5.A25.7B3.B2AB3A81.A.5A2.B8.5B$4.3AB2.BA5B.BA
.A25.6B6.B4.A63.A18.A4.AB2A6.6B$3.A.BA3.3A4B.B2A27.6B4.2A.3A62.3A17.A
2.BA.A.2A4.8B$3.2A4BA6BA2B29.5B4.A2.2A63.A19.A.2BA.A2.13B$.2A2.B2AB2A
2B2A2BAB28.8B.A.A66.2A18.2A.2BA5.13B$A2.3AB.BA9B19.A8.8BA.A.2A.A86.3B
3.15B$2A.A.A3.BA5BA2B19.3A3B3.6B.2BAB.A.2A67.A19.2B3.6BA8B$3.A8.3BA4B
21.A3B.2B3A2B2.2B2.A70.3A16.4B.6B2A9B$3.2A7.2A7B19.2A8BA2B3.B.2A73.A
8.14B2A13B$13.3B2.4B18.9B3AB2.A.A2.2A70.2A7.4BD10BA15B$11.5B3.4B19.
11B2.2A2.A2.A58.A10.5B.B2.4B3D8B3A14B$11.2A7.4B17.12B7.2A58.3A11.6B.
4BDBD20B3.B2A7.2A$12.A8.4B16.12B66.A2.2A9.14BD19B4.A2.A5.B2AB$9.3A10.
4B15.11B59.A6.2A11.20B2.2B2.B3.6B5.2A.A5.2A6.B$9.A13.4B13.12B9.2A33.
2A12.A.A5.A.A2.2A4.B2A16B14.6B7.A6.2A4.3B$24.4B9.2B.13B8.A35.A11.A2.
2A5.2A.2A.A2.A3BA13B14.7B2A6.2A4.3A11B$25.4B7.18B4.BA.A35.A.A9.A2.A7.
A5.A.ABA3BA10B15.2A4.2A2B11.BAB2A5B2A2B$26.3BA3.23B2.B2A37.2A8.2A15.A
4.4BA10B16.A5.BA2B.B5.5BA2B2A3B3AB$27.B2A5BA7BABA13B20.A29.2A10.A3.A
6.6B.8B11.3A7.14B3A8BA2B$28.ABA5BA6BA2BA13B19.3A10.2A27.A.A10.4B3.B3.
2A11.A9.13BA4B2A2B2A6B$29.7B2A8BA13B22.A7.2B2AB38.B2A2B7.A22.13BA8B2A
7B$30.6B2A2B2A4BA13B9.A11.2A3.B3.4B10.A.A27.2A10.3A19.13BA2BA6BA5BABA
$32.2BA8B3A14B7.3A11.8B.6B6.A3.A10.2A29.A20.13BABA7BA5B2AB$33.B3A3B2A
2BA5B5.B.2BAB5.A16.10BA4B4.A15.2A8.2A37.2AB2.23B3.A3B$33.2B2A5B2ABAB
11.2B2A4.2A15.10BA3BABA.A5.A7.A2.A9.A.A35.A.AB4.18B7.4B$33.11B3A4.2A
6.2A7B14.13BA3BA2.A.2A.2A5.2A2.A11.A35.A8.13B.2B9.4B$37.3B4.2A6.A7.6B
14.16B2AB4.2A2.A.A5.A.A12.2A33.2A9.12B13.4B13.A$38.B6.2A5.A.2A5.6B3.B
2.2B2.20B11.2A6.A59.11B15.4B10.3A$44.B2AB5.A2.A4.19BD14B9.2A2.A66.12B
16.4B8.A$45.2A7.2AB3.20BDBD4B.6B11.3A58.2A7.12B17.4B7.2A$55.14B3A8B3D
4B2.B.5B10.A58.A2.A2.2A2.11B19.4B3.5B$56.15BA10BD4B7.2A70.2A2.A.A2.B
3A9B18.4B2.3B$57.13B2A14B8.A73.2A.B3.2BA8B2A19.7B2A7.2A$57.9B2A6B.4B
16.3A70.A2.2B2.2B3A2B.3BA21.4BA3B8.A$58.8BA6B3.2B19.A67.2A.A.BA2B.6B
3.3B3A19.2BA5BAB3.A.A.2A$58.15B3.3B86.A.2A.A.A8B8.A19.9BAB.B3A2.A$59.
13B5.A2B.2A18.2A66.A.A.8B28.BA2B2A2B2AB2AB2.2A$61.13B2.A.A2B.A19.A63.
2A2.A4.5B29.2BA6BA4B2A$60.8B4.2A.A.AB2.A17.3A62.3A.2A4.6B27.2AB.4B3A
3.AB.A$60.6B6.2ABA4.A18.A63.A4.B6.6B25.A.AB.5BAB2.B3A$60.5B8.B2.5A.A
81.3AB2AB3.7B25.A5.4B4.A$60.B.B5.2A.A.2A.A4.A.A82.A.2AB.8B25.2A5.B3A
5.5A$61.3B4.A.2A.A2.A.2A2.A87.10B31.2BAB10.A$60.B2AB11.2A.A.2A88.11B
29.4B9.A$61.2A107.8BAB5.2A22.4B10.2A$170.10B5.A22.4B$169.11B2.BA.A21.
4B$169.6BABA3B.B2A21.4B$168.7B3A5B22.4B$167.9BA6B21.4B$164.2B.16B20.
4B$163.2A18B19.4B$163.2AB.17B6.A10.4B$164.B.4B.8B2.4B5.3A7.4B$171.7B
4.4B7.A5.4B$172.6B5.4B5.2A4.4B$174.4B6.4B4.9B$176.3BA5.4B5.6B$177.BA.
A5.4B2.8B$178.A.A6.8BA6B$179.A8.5B2A7B$180.3A6.5BA7B$182.A7.10B.B2A$
192.2BA2BA3.BA.A$192.3B2AB6.A$194.4B6.2A$194.3B$191.AB.2B$190.A.AB2AB
$190.A.ABABAB$187.2A.A.A.A.A2.A$187.A2.A2.2A.4A$189.2A4.A$195.A.A$
196.2A!