Once the sun had set and the curtains of night descended upon the city, Shishigou got to work straight away. To start with, he laid out a bounded field around the graveyard to turn people away; the ritual for the field was not very complex, as it only needed to hold until the summoning was complete.
Next, using a chalk distilled from the dusted bones and blood of magi, he drew a magic ward: a ring of purification carved around a ring of four purging circles, surrounding a ward of summoning. In the center, he placed a crystal ball. It was an all-or-nothing ritual, but Shishigou nodded in satisfaction at the quality of his work.
The only things left now are the the catalyst to be offered and the incantation for the spell. At first glance, this may appear all too simple for a ritual meant to evoke a Heroic Spirit. However, as the Master is nothing more than the string which ties the Grail and the Servant together, this will not prove to be a problem.