The solution to this challenge was written up by Madness, and with his permission I have added it to our library of resources. You can find it here.

The challenge below was a special 10th round for the 2020 Special Edition, with its existence and location hidden in the solution to Challenge 9B. It was a new cipher developed by Harry especially for the competition and, as expected, it was VERY hard. We promised Cipher Elite status to the first ten to crack it and they were:

Madness (no surprise there)
Some successful sister’s senior sibling
Kalicali
Cribbage
Puttputt86
Cricguru + Jaysong
Bumble
Berceuse
Susan
AdupthetotalCracks

You have joined an elite band of cryptanalysts who have cracked the final round of a BOSS training mission. Or have you? Clearly the story can’t end there, and if you want to read the final instalment before everyone else gets to, then you will have to crack one final code. You solved part of the puzzle by finding this page. Now you have to use all your skill to break the cipher protecting the attached report from Swallow, which details the final adventure. It is like nothing you have seen before in this edition of the competition, but I will tell you that it is inspired by the simple combination lock!

If you can’t crack it don’t worry, you did well to find this page. Let Harry know you got that far on the forum by posting the codeword ELITE. We will publish the solution here at the end of the competition [which is when I say it is – Muhaha! Harry]

No feedback, no marks, no submission form – no help from us at all. You are all alone! If you get the solution, email it to Harry. The first ten people/teams who crack it will be awarded the accolade of Cipher ELITE. Good luck!

Cipher Challenge 2020SE – The Elite Challenge

UHKLC BRHEB URAAG @@QLA KLHAR @JCAI LBLQU DNAET @F@JL CEARQ @C@VR DBLVC FBCAM AGDBR Q@RHE BFEBV YAUBS ET@OS OCVCR KOLBC @PADI RZA@S BRHEB OM@MT BIRB@ EE@MD BCLCB S@RQ@ RHEBL BYK@O FFICI @MRAR HBSBR HEBF@ DRQRX AUBSA LQ@LO LHDT@ RAGCB CJCB@ MCFEN JRSEN BUETC BILHO RLDEA @MEAR ULCEA RHBSB RHEBL PCDT@ SQR@U QULCA @EBRA GCT@R SQRCE AILBF DTLAM ZAUHE TCBIR BUQUL CA@MR P@@EB CLORD T@RQ@ RHEKR @CZOD TILDN TBM@F @DILI RKCTS HEBOO DT@SK OLBRQ @LPUD BRHEB RCNAJ LKLHA RSQCI TAOF@ OPRBS SJULA FZDSO XICDB FROLA UHKCF BRHEB FEBVY AUBSE T@UBS ARQ@@ EBCZR T@DRE EAUBS AOM@M NEEAF OR@LJ CGCBT U@SXA @MEA@ QRSAU BSA@M CTREE ARQ@R HEBOM @MB@Z ALDNA ETRAO F@RHE BRVBM LOUBR EBMAU HQ@RC NAJLE EAILB COLTB DRBUK RHBLO XAM@L QRUEH J@MTA UQRIK LHA@S BRHEB OM@MT BRHEK R@ILT EN@@M LOUEE A@ACO ULTET OODT@ SKOLB RQ@@E BOSCQ ASCEJ LKRK@ M@RVR UDKLL @MECB RGQUE EARHB SBRDE URIRZ AOLBR HEBR@ JL@LI LEBRH BSBUQ ULCAC @SRXA RHEBC @SFP@ FBDA@ EENBR SEQPD EAUOA FOLLO UKLHA RHEB@ QLAKL HAR@J CSAUK RHBLO C@M@C IUJLI @MTAL Q@LOL HDT@@ MLOUE EARQ@ RT@VD N@OLB RHEBR T@JLT A@MEA ILERC BSDEA FV@SC AOAST OLRAR AAQRB GDBOF @RHEB R@JLU BYALI LEBUB SALQR BFCBS J@NCB @MEAI LB@MZ AC@SD BIRBU QULCA @EBCJ FFICU LRBRQ @OM@M TB@AC FBSFD BCJRS UOSKU DBCNQ UFGBR Q@CAM AGDBR HEBC@ SFP@A CDEIR JOLBU BSARB JENBI LTSEB DARQ@ LJLEB RHEBF WLL@O F@RHE BRG@F ZDSO@ @QRSA @GDNT TAILB RHEBO M@MTB UETCB @ANCB RQ@CD TETLJ LEBRH EBRGK OPJLH ACASE B@MEA ILBOR CDT@R Q@LJL KLJXE BCIUJ LI@MB C@SV@ MRKCT AIKDN L@LKC NRDNB CDN@Y DEARH EBCDE @MTBO F@RHE BOPRB SSJUL AFZDS OXICD BFROL ARHEB RSQR@ GDBRB MKTAI LKRK@ MLXAR HEBRS AFBDA FQODE ARQ@R GKOAO LBRHE BRASW RCAYA UHENB RHEBF CTRIC TAUET CBRZP JC@ML XAUDT XA@WR YARHE BCDN@ YALPU DEARH EBRGK OMDNT BRQ@R VLEAY ARCEV CILHA RHEBL WLAET @OF@O ASSDN HDTRA ZARJL KKLHA RHEBF CTRXA ILBRH EBCDE QDTSB OASRB OF@L@ JEBRK LNBRH EBRAA QREWR RAFQO DBRQ@ OSCWD NTBRH EBLBY KRAFR OLARC EOUDT ILHAR HEBC@ SFP@C ZODTI LDNTT ACOLW JLECE ARHEN ARHBS BRHEB LPRSB CHFCE RKUDB UBYAR Q@CNT VRCBR HBSBR HEBFC TRXAC OULCA LQRB@ EBRCT DUCEA UBSAR Q@@NO UBOUR B@ARP W@SCB RDERK OLBOF @RHEB FWLL@ @ZARH EBOSO UB@ZA RJLKK LHARH EBOSO UBFIR RSBRH EBRGK OSARS EET@G DBUQU LCA@E BLIFR EEAOU RBOF@ RHEBU BSET@ LCBVJ LHARH EBCRC WBUKR HBLQ@ COLTT OL@RH EBREB MAUET CBCDT ETLJL EEARH BSBUH KLCBR HEBCZ OMORJ OLBFB DARQ@ @EBL@ SFDBC NQUFG BRQ@C @VRDB F@SBM @CAMA GDBRQ @RHEB RGKOA IRBFB DARQ@ LCBVD BRKLD BFOR@ RHEBO ASSDN HDTRA @MEAC RCWBR Q@CWA DU@SE BRHEZ A@WIL RBRHE B@QLA BFROL ACKFG TEENB OPULE SAOF@ OM@SS KC@IL KRK@M @OM@M TARQ@ URDBF URDTA LCHRB OUDT@ FROLA RHEBR VCCCT SGUL@ UDNPR IBRAA QRBGD BOODT @SKOL BUETC BRQO@ RGQRR BFOR@ RHKRA @SARH EBRGK OAUQU LCARS KLL@@ EBCLO RDBRQ @RGQR CBUHE NBRHE BCZOM ORJUD TAUEN TBOFF @RP@R HEBRE BMAIL PSOUJ RDEA@ ARKLJ LHACD WJCCB URJLH A@MB@ M@SLA CLOCI BRHEB RPW@D ACOLT JRSKL HAOF@ @MF@L @SRDN BINWR BLICT FBMTD NBROL F@RPR LICB@ MEAIN WRBFB VIENI CA@SS DNANC EA@AF CWBIK LOLDT TCTAF ROLAR HEBOW @YA@S BLADN @@MEA @PPSO @DFEE A@SBL KFGTB RHEZA CURBR HTOUF GB@AF CNECB @MEA@ Q@SCD EARHE BRGKO AUHET CBRHE ZAUET CBCJR DOUDT CEA@Z A@AOA STOL@ LICTF BMTDN BRTIC EARQ@ COLWJ LECBR HEBFV @SCAR HBSBR HEZAU ETCBO ASSDN HDTRA UHQ@I VRSBU BMTEE ARQ@R MCEQA OLBRH EB@Q@ SB@WR BFEBU BSAUL EOLWJ LECEA RDNTJ LHARH BSBRH EBFEB LJFGT B@EBR YMPAS HETKC @RHEB REBMA @DMJR TEEAR HBSBR HEZAU QRIEE AFOR@ RHEBR CTJRS BMECB @MEAR QLCAR HEBFV @SCAR HEZAL EEEDE ARQ@@ EB@ML OUEEA RQ@FK CDBRP LDTHK LHAOL BRHEB RGKOA RHKRA UQRIE EA@ME ARPRL ICB@M EAFBV IENIC AUETC BODTL JRTEE ARQ@F P@@EN OUBCD EIBRQ @RHEB IEEN@ UHETC BRHEZ ARPDN TBRHE BLEZR BRWQ@ FQURR AOM@D ILHAC ZOMOR JUDTA UHENB RHEZA FBDAF ILKRG EEARH EBRAA QREWR RALCH RBRHE BRGKO AUKRH QURB@ MZAFU RRHET @CFBM LCNHD THEBL EZRBL PRLKL HARHE BCDWJ CCBCZ OMOCD EA@SA OM@MN EEAIV RSB@S ARHEB L@DDN BRGKO ARCBD FEEAR HEBUR CAMCN BLIFG THQUR DBIRB RWRLE EAILM DEJ@S ENXAF OR@RG QRCB@ WRBRH EBCAM AGDBU BSARQ O@RDW DTCB@ MEARH EBRGK OALIR SEEAO WICIN XARHE BRGKO ARAMK B@SBR ENBRH KRRZA RDTTN ILHAO LBRHE B@QRT QLAIL BFOUR @FWLE SCEA@ MEARH KRRZA LDTET RARHE BLIFC BQ@ST AUETC BLQRB CDQMO XDEA@ MEAOA SSDNH DTRA@ MEACR CWBFB DALQ@ ILTST UCRKO LTAOL BRHEB URDBO F@LIF CBENR TARP@ C@SV@ MRKCT AUETC BULBV PICAA NCB@W RBF@S LDTRA FROLA @DROR SARHE BL@JE BC@MD BRQ@R HEBRC TDUCB OF@RH EBCRC WB@ME AOASS DNHDT RAFOU RREEN BLQRU EHJ@M BCRCW B@MEA OASSD NHDTR A@MEA FOUR@ FDTLA MBRPL CJCTR ACJCE A@MEA CKFGT BCAYS A@GRE T@RHE BILEI CDNTB OASSD NHDTR A@MEA CRCWB OF@RH EBRG@ RIVIB MHORA LASIE EARHE BRJLK KLHAU KRHB@ ALDNP RI@M@ RDTUJ CCTHE BC@SV @MRKC TAUET CBLPR SBRCH SCTTB ANCB@ WRBRH EKR@C DBSHT AUETC BLQRB ILBUA JLBRH EBC@S FP@UB SACDT STOXD EA@ME AIRBI RALII ENXAR HBSBR HKRAU KLL@L ASIB@ MBCNE ARQ@R HEBFD TLAMB LWCLC BS@UE BPPLT AOSOF S@MMD B