In addition to St Catherine of Siena, today (April 29) is the memorial of St Peter the Martyr, O.P. (+1252), who received his habit from St Dominic Guzman himself. St Peter was a Dominican inquisitor and wonderworker who preached against the Albigensians and Cathars and is traditionally held to be the first Dominican martyr, hence THE martyr.
St Peter has the honor(?) of being consistently portrayed with the instrument of his death firmly lodged in his skull,—even when not actually depicting his martyrdom!—and usually a blade piercing his shoulder as well, such as in the painting below where he is honoring our Lady with the Child Jesus and John the Baptist.
And as if that weren’t intense enough, it is told that he wrote Credo in Deum, “I believe in (one) God,” in the ground in his blood and forgave his attackers in the words of the Protomartyr, St Stephen, as he died at the hand of Cathars at the age of 47.