this poetry, had risen to influential positions by the Vijayanagara period. Following the Muslim invasions in the early 14th century, Brahmin scholars methodically consolidated writings of Hindu lore. This inspired several Veerashaiva anthologists of the 15th and 16th centuries to collect Shaiva writings and poems, originally written on palm leaf manuscripts. Because of the cryptic nature of the poems, the anthologists added commentaries to them, thereby providing their hidden meaning and esoteric significance. An interesting aspect of this anthological work was the translation of the Shaiva canon into Sanskrit, bringing it into the sphere of the Sanskritic cultural order. Well known among these anthologies are by Kallumathada Prabhudeva (1430), by Channaviracharya (16th century) and by Siddha Basavaraja (1600). The unique (the 'mystical zero') was compiled in four versions. The first among them was anthologised by Shivaganaprasadi Mahadevaiah (1400), who set the pattern for the other three to follow. The poems in this anthology are essentially in the form of dialogues between patron saint Allama Prabhu and famous (devotees), and was meant to rekindle the revolutionary spirit of the 12th century. Halage Arya (1500–1530), Gummalapura Siddhalinga Yati (1560) and Gulur Siddaveeranodaya (1570) produced the later versions. Though the writing of poems went into decline after the passing of the Basavanna era in the late 12th century, latter day such as Tontada Siddhesavara (or Siddhalinga Yati), a noted Shaiva saint and guru of King Virupaksha Raya II, started a revival. He wrote (1540), a collection of 700 poems. In 1560, Virakta Tontadarya made the life of Tontada Siddhesavara the central theme in his writing . Virakta Tontadarya, Gummalapura Siddhalinga, Swatantra Siddhalingeshwara (1560) and Ghanalingideva (1560) are some well-known poets who tried to recreate the glory days of the early poets, though the socio-political expediency did not exist. Mystic literature had a resurgence towards the beginning of the 15th century, in an attempt to synthesise the Veerashaiva and advaitha (monistic) philosophies; this trend continued into the 19th century. Prominent among these mystics was Nijaguna Shivayogi, by tradition a petty chieftain near the Kollegal region (modern Mysore district) turned Shaiva saint, who composed devotional songs collectively known as (or , literally "songs of the pathway to emancipation"). Shivayogi's songs were reflective, philosophical and concerned with yoga. They were written in almost all the native metres of Kannada language with the exception of metre. Shivayogi's other writings include a scientific encyclopedia called , so well