Freemason Cromwell mounts a battering ram, grape shot, and bullets against Blarney castle. The Irish have bows and arrows. Cromwell "made a dark signal" freezing the defenders. He and his soldiers walk across the lake. He gives Jeffreys the Castle
Croker-PopularSongs: "Upon the allusion made to Oliver Cromwell in the second and sixth verses, it is necessary to remark that, according to the popular belief of the Irish peasant, Cromwell was endowed with supernatural powers; and that the fraternity of Freemasons, which was said to be founded by him, were supposed, from the secrecy and ceremonies obseved by them, to be dabblers in the black art."
Croker-PopularSongs: "The name of Cromwell, although associated both in song and story with the taking of Blarney Castle, is obviously used for that of his partisan, Lord Broghill (afterwards the Earl of Orrery). Cromwell, if indeed he ever was at Blarney, could only have paid it a short and peaceable visit."
Croker-PopularSongs: "The Editor has no doubt that this song, and ['Saint Patrick's Arrival'], came from the same pen." See that song if you are interested in Croker's speculations there. However, Croker notes that the song has been "unceremoniously appropriated by Father Prout [Rev Francis Sylvester Mahony (1804-1866)]." Croker prints alternative verses from Father Prout's version. In both versions the castle is given by Cromwell to Jeffreys but, according to Croker, the Jeffreys family purchased the estate from the crown (source: "Blarney Castle" in _The Mirror of Literature, Amusement, and Instruction Volume 14, No. 396, Saturday, October 31, 1829_, on the Project Gutenberg site quoting Croker, _Researches in the South of Ireland_) - BS
For some background on the horrors inflicted on Ireland by Cromwell, see "The Wexford Massacre."
The fear and hatred Cromwell inspired is reflected in later Irish culture; mothers would threaten their misbehaving children: if they didn't stop, "Oliver Cromwell will get you." - RBW