The history pages tell the community's story in
order; this page tells it by person. Nearly everything this wiki knows
(every record, theory, tool and
documented dead end) traces back to someone who
posted it on the eternity2 mailing list,
usually for free, often for years. Consider this gallery an index and a
thank-you at the same time. Names appear as people signed their public
posts; every claim links to a message.
Many of the people below have their own contributor page: a name in bold
with a link opens it, gathering their profile, their sourced posts, and any
pages they have written here. Raphaël Anjou,
who maintains the wiki and runs the lab experiments, has one too, one
researcher among the others. The names without a link are documented right
here, on this page.
The founder. Owen created the eternity_two group in October 2000, six and a
half years before the puzzle existed
(msg 384), and set its
scientific tone: within two days of the January 2007 announcement he had
derived the expected-solutions formula that makes difficulty a design
parameter (msg 38), and on
launch weekend he digitized the real pieces and published the first
solution-count estimate
(msg 987). His signature
results: the proof that a 17+5 colour split is the hardest possible 16×16
(msg 1947), the exact
search-tree model now called
complex theory
(msg 5197,
msg 5209), the 9×9/10×10
benchmark puzzles the community still races
on, and the closed-form
peak-depth proof 256 × (1 − 1/e)
(msg 8125). After a farewell
at the contest's close
(msg 8429) he returned in
2025, refining his own model
(msg 11500,
msg 11546).
An Eternity I veteran and the group's earliest provocateur of estimates: in
2001 he asked, years ahead of the fact, how one would design a puzzle with a
huge prize and only a ~1% chance of being solved in ten years
(msg 15), and he greeted the
2005 press claims with "So we can conclude, the end of the universe is in
several years." (msg 34). For
two decades he checked the list's numbers, from exact-cover conversions in
2007 to the nodes-per-watt hardware ledger of the 2010s.
Author of the distributed Eternity I solver ESolve, he rejoined in 2001
(msg 21) and built eternity2.net,
the BOINC project that was the community's public face in 2007
(msg 756). He shut it down with
full accounting: 1.6 TFlops, over 10^19 operations, no solution
(msg 3511). He open-sourced
his solver (msg 3716) and left
the archive its best primary source on the puzzle's creation: his phone call
with Monckton describing how the solution was generated and vaulted
(msg 4177).
Angel de Vicente, who signed Txibilis, built the standard suite of E2-like
benchmark boards (msg 1886)
and was the community's best hand-designer of
fill orders. His duel with
doc_s_smith's automated optimizer drove full-search node counts down by
orders of magnitude
(msg 2928). The benchmark
culture that later validated complex theory starts with him.
Mid-duel, the list discovered who doc_s_smith was: Dietmar Wolz, finder of
most of the known Eternity I solutions
(msg 2972). His automated
strategy optimizer set benchmark records in 2007
(msg 2896); returning in 2010
he published a Java toolbox that turned the list into an algorithms workshop
(msg 7755) and gave the
post-contest era its working goal: "beat 468 matching edges"
(msg 7803).
Author of the first serious solution-count paper, putting E2 near 15 million
solutions (msg 3497), and of
the era's cleanest impossibility result: the parity argument that no board can
score exactly 479 by its interior seams
(msg 1640). It held for seventeen
months, until Verhaard pointed out the one loophole
(msg 6317): flip a border piece
whose two outward border edges share a colour, and the board reads as 479 while
those unscored rim edges go untouched. That is a technicality of the unscored
border, not a break in the interior-parity math, which still holds, as Verhaard
himself noted that 479 "cannot be achieved in another way"
(msg 6319).
Michael Quist was the list's mathematical referee. He posted the first fully
rigorous counting framework for E2-like puzzles
(msg 1221), sharpened the
border-balance theory
(msg 2098), and his reviews
caught the flaws that made others' results solid. Kubzpa amended his
solution-count paper after his pass caught a flawed Monte Carlo run
(msg 3589).
The only person the puzzle ever paid. His eii solver, released publicly
"because I am stuck"
(msg 5940), found the 467
that won the $10,000 scrutiny prize, entered under the name of his wife,
Anna Karlsson, as he confirmed himself: "Anna is my wife… it was my program
that did the job"
(msg 6349,
msg 6891,
msg 7451). His methods became
canon: comb-search fill orders
(msg 6112) and depth-gated
edge slipping (msg 7321). He
was also complex theory's staunchest defender: "the finest work that has
ever been published about E2"
(msg 7810), and his 467 stood
for twelve years.
Author of the Eternity II Editor, the cross-platform Java editor and solver
GUI released in February 2008
(msg 4544) that became the
community's standard board tool for years. He was still offering help with
its code when it resurfaced in 2012
(msg 9064).
Posting as Eternity Blogger, Fred built E2Lab in a burst of near-daily
releases in autumn 2009 (msg 7148),
an editor/solver whose deliberate removal of its own "magic button", "to
respect the game rules", says a lot about the list's ethics
(msg 7150). His blog hosted
the community's tables through the post-contest years.
A regular since 2008 and the community's border theorist. His "balance
doctrine" for puzzle generation appears in 2009
(msg 6842,
msg 6844); in 2022 he stated
the exact condition this wiki calls the
NS-1 border balance
(msg 10754,
msg 10757), and backed it
with a fully documented 222-piece partial with completed border
(msg 10862).
The era's anchor, and arguably the puzzle's most consequential researcher
after Owen. His work has its own page.
He computed the canonical ~14,702 expected solutions
(msg 8924), transcribed
complex theory into LaTeX
(msg 9188) and later into
exact C code (msg 11197),
which this site ports. In 2017 he solved Owen's hint-free 10×10 in ~180
core-years, inside the theory's error bars, its strongest validation ever
(msg 9686,
msg 9688), and in 2020 he
held the record himself: "New record score of 469! Only 11 breaks!"
(msg 10045).
Academia in person. He posted his group's peer-reviewed hyper-heuristic
paper (461/480 in an hour) and stayed to answer questions
(msg 9017,
msg 9023), and his group
followed with the 2017 MILP and Max-Clique work
(msg 9683).
A fastest-solver veteran of the early years who became the group's hardware
realist: his FPGA backtracker design projected ~5G placements per second per
chip (msg 9226), and his
capacity analyses of GPU and FPGA routes told the list what silicon could
and could not buy (msg 9003).
Arrived in 2009 and reset the speed standard in 2014 with a 114.5 million
recursions per second single-core solver offered as a comparison baseline
(msg 9233), returning in 2018
for the benchmark races.
The GPU flank. Arriving in 2017, he moved from CPU bit-tricks to a DirectX
12 compute solver running on an Xbox One X
(msg 9811) and re-verified
Owen's 9×9 set 1 exhaustively on GPU: the same 2 solutions as the 2014 CPU
census, in 25.4 hours
(msg 9822).
The community's verifier and, later, its rescuer. In 2009 he reproduced the
467 with Verhaard's public solver, ~82 days on one PC, logging exactly how
thin the air gets above 466
(msg 6687). When Yahoo
announced it would erase the archive in 2019, JSA paid the groups.io
transfer fee, offering "I can pay for the first 5 years"
(msg 2), and he still writes the
group's welcome notes
(msg 11771).
Kronjuvel (Kron) was there from the earliest years, retro-claimed a
231-piece partial from October 2007
(msg 7563), and as group owner
created the new groups.io home during the 2019 migration. The 2026 welcome
note opens with a tribute to him; he has been missing from the list since
2023 (msg 11771).
The outsider who ended the twelve-year freeze. Unknown to the list, he
announced a 468 on Reddit in August 2020
(msg 10032), open-sourced his
solver days later (msg 10037)
along with rare negative results (SAT, GPU and 2×2 caches all measured and
discarded, msg 10056), and
in March 2021 posted the 470 that still stands
(msg 10117), found with the
exact public code (msg 10161).
His algorithm is decoded on this wiki.
The modern era's infrastructure. He raised the alarm that triggered the
archive migration (msg 9920),
built the e2.bucas.name board viewer that became
the community's record book
(msg 9955), rewrote
Blackwood's solver in C as libblackwood, roughly doubling its speed and
powering the November 2020 wave of 469s
(msg 10065,
msg 10078,
msg 10067), and tied the 470
in 2024 (msg 11401), always
crediting Blackwood. His wrapper_blackwood parameter study is republished
on this wiki with his permission
(msg 11905).
The board surgeon. He produced a 469 by a single-piece swap of McGavin's
record board (msg 10074), a
border-rearranged 470 variant
(msg 11403), four-minute
14×14 quadrant solves
(msg 10802), and high rungs
of the five-clue ladder
(msg 11068).
A speed veteran of the 2014 era whose Forth solver ran at 80–90 million
nodes per second (msg 9265),
he held the strictest record on the books for over three years: 460/480 with
all five clue pieces at their official positions, from 2023
(msg 11074) until Benjamin
Riotte's 464 in July 2026.
Holder of the strict five-clue record. In July 2026 he pushed the best board
respecting all five clue placements from Gauthier's long-standing 460 to
464/480 (16 broken edges), with his own modified-Blackwood DFS
(groups.io). Igor Pejic
reached the same 463–464 range independently in the same thread. It was the
first movement on the strict-canonical line in over three years.
The SAT world's contact point. In the long-running SAT thread, a
collaborator of Marijn Heule reported that Heule's group had re-implemented
and improved the encoding behind the 2008 SAT benchmark results
(msg 10969), the
state of the art of the exact-methods flank, which was still debating
4 GB CNF encodings on the archive's very last day
(msg 11822).
Maintains this wiki and runs the experiments catalogued in
the lab; his write-ups gather on his
contributor page, one researcher among the
others.
Ran a dense two-week solver campaign in 2026, most of it recorded as
refutations of methods that do not crack the puzzle. Two of his findings sharpen
the ceiling: a replica freeze test, and a halo SAT-residual test showing the
record boards are strict local optima. We reproduced the second on the public
boards, and it lands on the
rigidity wall alongside the integer-programming
proofs
(reproduction).
Founded the community's Discord server in November 2021 and kept it alive
through the quiet years (reported on the community Discord, November 2021; no
public message link). A dedicated solver
in his own right (self-reported best around 466–467), he is also the reason
the wiki once mis-carried a "2025 470": a record relay misread as a
record claim, corrected here from the Discord archive itself.
The Discord era's methodical hunter: a self-reported best of 469, the
linear-run subculture (229- and 230-piece consecutive partials), and the man
who settled where the hint placements come from: "They directly come from
Tomy's Hint Puzzles" (reported on the community Discord, December 2024; no
public message link). On the mailing list he confirms storing solution figures
scoring above 467/480 (msg 11549).
His suggestions also shaped this site's playground roadmap.
No gallery this size is complete. Among the many who belong here: Alan
O'Donnell, who had the first working solver weeks after the announcement
(msg 64); Max, Verhaard's
sparring partner in the run to 467, whose own best was 465
(msg 6348); istarinz, who
broke 558 million placements per second in 2008 and became the group's
exhaustive-search verification authority
(msg 6212); antminder, whose
assignment-repair hybrid averaged a 462 per day in 2008
(msg 5589); Pierre Schaus,
whose constraint-programming paper supplied that repair operator
(msg 5601); capiman26061973,
founder of the five-clue ladder
(msg 11037) and the
invalid-combination mining programme
(msg 7768); David Barr,
open-source GPU and browser solvers across a decade
(msg 9367,
msg 11121); Henk van der
Griendt, who found the prize announcement everyone else had missed
(msg 6337); and
juraj.pivovarov, the community's rapid-prototyping conscience
(msg 9411).
This page will always be incomplete, and it may be wrong in places: a
misattributed result, a missing name, a preferred spelling. If any of it
concerns you or your work, please say so on the
mailing list or through the
contribute page: corrections land with the same
sourcing rules as everything else here, and credit is the whole point of
this page.