Guerrilla warfare, also spelled guerilla warfare, is a type of warfare fought by irregulars in fast-moving, small-scale actions against orthodox military and police forces and, on occasion, against rival insurgent forces, either independently or in conjunction with a larger political-military strategy.
Shivaji pioneered Shiva sutra or Ganimi Kava (guerrilla tactics) against the Mughals and other powers in 1645 leading to the establishment of the Maratha state in 1674, sowing seeds of what would become the last major Indian empire, the Maratha empire, before the British Raj.
Final Answer: The Marathas fought guerrilla warfare.