In the spirit of the What is a Word™/Phrase™ series started by JLee, a special brand of Phrase™ and Word™ puzzles.
The quest Ryan was on brought him to the final clue he needed: "If a word conforms to a special rule, I call it a Quest Word™.
Use the examples below to find the rule."
$$ % set Title text. (spaces around the text ARE important; do not remove.) % increase Pad value only if your entries are longer than the title bar. % \def\Pad{\P{0.5}} \def\Title{\textbf{ Quest }} % \def\S#1#2{\Space{#1}{20px}{#2px}}\def\P#1{\V{#1em}}\ \def\V#1{\S{#1}{9}} \def\T{\Title\textbf{Words }^™\Pad}\def\NT{\Pad\textbf{Not}\T\ }\displaystyle \smash{\lower{29px}\bbox[yellow]{\phantom{\rlap{rubio.2017.02.04}\S{6px}{0} \begin{array}{cc}\Pad\T&\NT\\\end{array}}}}\atop\def\V#1{\S{#1}{5}} \begin{array}{|c|c|}\hline\Pad\T&\NT\\\hline % \text{QUEST}&\text{ADVENTURE}\\\hline \text{TRIANGLE}&\text{SQUARE}\\\hline \text{ESTABLISH}&\text{CREATE}\\\hline \text{STRENGTH}&\text{INTELLECT}\\\hline \text{QUESADILLA}&\text{ENCHILADA}\\\hline \text{EQUALITY}&\text{CORRUPTION}\\\hline \text{TRIPLE}&\text{DOUBLE}\\\hline \text{STRIPES}&\text{DOTS}\\\hline \text{PEDESTRIAN}&\text{WALKER}\\\hline \text{QUEUES}&\text{LINES}\\\hline \text{SEQUITUR}&\text{SENSIBLE}\\\hline \text{PEST}&\text{NUISANCE}\\\hline \text{PROTEST}&\text{ACTIVISM}\\\hline \text{ASTRONOMY}&\text{STARGAZING}\\\hline \text{ASTROLOGY}&\text{HOROSCOPE}\\\hline \text{TRIAGE}&\text{PRIORITIES}\\\hline \text{EQUIPMENT}&\text{WEAPONS}\\\hline \text{CHEQUES}&\text{BILLS}\\\hline \text{RESTRAINT}&\text{FORWARDNESS}\\\hline \text{TRIM}&\text{HAIRCUT}\\\hline \end{array}$$
CSV Version:
QUEST,ADVENTURE
TRIANGLE,SQUARE
ESTABLISH,CREATE
STRENGTH,INTELLECT
QUESADILLA,ENCHILADA
EQUALITY,CORRUPTION
TRIPLE,DOUBLE
STRIPES,DOTS
PEDESTRIAN,WALKER
QUEUES,LINES
SEQUITUR,SENSIBLE
PEST,NUISANCE
PROTEST,ACTIVISM
ASTRONOMY,STARGAZING
ASTROLOGY,HOROSCOPE
TRIAGE,PRIORITIES
EQUIPMENT,WEAPONS
CHEQUES,BILLS
RESTRAINT,FORWARDNESS
TRIM,HAIRCUT
The puzzle satisfies the series' inbuilt assumption, that each word can be tested for whether it is a Quest Word™ without relying on the other words.
These are not the only examples of Quest Words™, many more exist.