The Font was the altar in the middle of the Nightsister fortress on Dathomir. It was where the Nightsister witches, specifically Mother Talzin and her coven of spellcasters, would perform their magic.
Asajj Ventress was healed on the Font with the Water of Life upon returning to the Nightsisters. The Font was also where the Nightbrother Savage Opress was transformed into an avatar of primal anger, to serve in Ventress's plot for revenge on her former Master, Count Dooku. Later, Mother Talzin healed the deranged Darth Maul's mind on the Font, and also used her magic to graft cybernetic legs for him.