Sense Quintessence( Monster Manual V, p. 110)
You are capable of discerning sources of quintessence, a magic substance precious to Thoon.
Affilitation with Thoon, Detect magic (as spell or spell-like ability),
Whin you use detect magic, you also detect any quantities of quintessence within the spell area. 1st Round: Presence or Absence of Quintessence. 2nd round: Number of different Quintessence sources, and Size and potency (moderate or strong) of the mot powerful quintessence source. 3rd round: the location of each quintessence source.