bitcoin hash program for other uses

[jerethdaminer]

while the topic makes next to know sense im asking for help
i have some encrypted text from a very old game called perplexcity and i want to crack it i know the key is 8 characters but i have no idea how to modify or write a program to brute force it using well gpus

it stands to reason that the bitcoin miners work on a similar basis i was hoping  someone might be able to help me out

the text  looks likes hex code and ill transscribe it in a moment but the top has 64/12/8 above the block and 5 cows on the bottom
the card was called the 13th labor

text block begins :

69 A9 3A FD C5 AD 43 8F 48 53 56 0F
1D 35 3A 8C 5C 44 A6 90 1B 76 46 C7
65 53 C8 A1 E4 B0 40 41 85 2B B7 81
59 E0 D2 39 35 A3 27 3B C3 AF 2E 2E
2F 3B 3B 0B 01 F1 67 51 FE 73 A8 E9
36 0A 93 85 55 2E 9A 4A AE C9 84 CF
18 F8 AB 4D B5 6D 45 07 4E 17 23 A5
7C F1 E8 BD A5 8A BD C8 FE FC DA 2B
6B 71 76 88 1F CO D1 95 61 8D DB DC
D8 17 2E D7 1D D5 F7 AB AD AB 3E 52
2A 22 AE 72 85 4A 43 1F 7C 2A BF 2A
A2 22 AE 72 85 4A 43 1F 7C 2A BF 2A
79 3A 15 03 8D F2 5B 43 98 90 6D CC
A0 BB E2 A9 6A 52 D1 CB 2B 83 DE D8
BF EC 20 11 70 71 AA 22


TEXT BLOCK ENDS:

any help would be appreciated
this card was solved via brute force solution a few years ago but the answer was never revealed
thanks

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[MysteryMiner]

Bitcoin miners use SHA256 function. Not much of that can be reused for other brute forcing purposes.

What encryption it uses? 8 characters are 64-bit key. Might be brutable on modern hardware.

[jerethdaminer]

RC5-64  it looks like

saddly im no programmer but i do know that an atempt was made to bruteforce it using only a-0 and it failed
was hoping some of the briliant people heere might have ideas seing as this is encryption