Path of Exile
Which ascendancies the top of each ladder is actually playing, refreshed
daily.
How this is measured
The Path of Exile ladder ranks by experience, so this measures what people
are playing at high level, not how well those characters perform —
there is no score or placement to read. It is the same measure as the WoW
class tier list, which counts specs among top-ranked teams, and tiers are
graded the same way: relative to the most-represented ascendancy in the
league.
Characters who have not ascended yet are excluded, since the ladder reports
their base class and a levelling Witch is not a peer of a Necromancer. On
hardcore ladders dead characters are excluded too — they have left the
league, so counting them would measure what died rather than what is being
played. Their death rate is shown separately.
There is deliberately no gear or passive-tree data here. Grinding Gear
Games' character endpoints stopped serving those to unauthenticated
callers, and the OAuth API that still exposes them is closed to new
applications, so ascendancy representation is the whole of what can be
measured honestly.