The Goddess of Lakes and Rivers. Also the goddess of Staff Thwapping, as illustrated here:
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,. /__ \[
||] |(@@)|| <--- Kastalia
|| \| \/ ||
|| '--|--'
|| |/\|\|
|| |
|| / \
*thwap* || | |
__(} | |
,-> _/ \_ _| |_
|
'--- mortal