Zendo, play by forum

[Proxima]

YEW
YBLUE
BLUEY
WOLLE
ELLOW

[Nepster]

White:
YA
YL

Black:
YO
YW
YOLO
YEW
YBLUE
BLUEY
WOLLE
ELLOW

[mobius]

L
LL
LOL
MISTER
MISS
MISSSS
MISO
ACK
ACHE

[Ramon]

WE
ALL
LIVE
IN
A
YELLOWSUBMARINE

[Nepster]

White:
MISTER
MISS
MISO
WE
IN

Black:
L
LL
LOL
MISSSS
ACK
ACHE
ALL
LIVE
A
YELLOWSUBMARINE

[Minim]

Let's try a few more longer words. BTW "LEMMINGS" wasn't even submitted as a koan guess yet, so I'll put that in for the name of the forum's sake.

LEMMINGS
CARELESS
CLICKING
COSTS
LIVES
LEMMINGOLOGY
SANCTUARY

[Clam]

MISTERYELLOW
MISSWHITE
TIMERS
WINE
SUBMARINE

[Nepster]

White:
MISTERYELLOW
TIMERS
WINE

Black:
LEMMINGS
CARELESS
CLICKING
COSTS
LIVES
LEMMINGOLOGY
SANCTUARY
MISSWHITE
SUBMARINE

[Proxima]

ZEMMINGS
YAAAAAAAAAAA (eleven As)
YAAAAAAAAAAAA (twelve As)
YOUNG

[Nepster]

All of them are black:
ZEMMINGS
YAAAAAAAAAAA (eleven As)
YAAAAAAAAAAAA (twelve As)
YOUNG

[Minim]

This is as hard as ccexplore's rule. I tried adding up the values, but that idea isn't working very well. I'll have a wild guess.

AKHTBN iff 50% or more of the letters in the word are from the second half of the alphabet (N-Z)

If not, I'll submit more koans instead.

NEWPORT
LONDEN
READING
BLACKBURN

[Nepster]

This is as hard as ccexplore's rule.

I expected it to be harder than Clam's round, but definitely easier than ccexplore's rule. But I might have underestimated the difficulty arising from the rarity of white koans.

AKHTBN iff 50% or more of the letters in the word are from the second half of the alphabet (N-Z)

No. A counterexample is NONSTOP, which is black. Alternatively the koan COSTS you asked last time would be a counterexample.

White:
LONDEN

Black:
NEWPORT
READING
BLACKBURN

[Proxima]

YAA
YEE
YY
YYY
YYYYYYYYYYYY (twelve Ys)
LIX 

[Nepster]

All of them are black.

[ccexplore]

LLOW
M
MI
MIS
MIST
MISTE
STER
YOLLEW
YLOELW