The forested volcano of Mahagnao in central Leyte Island is also known as Kasiboi or Casiboi. The andesitic volcano contains a steep-walled forested summit crater open to the south. Thermal areas with fumaroles and mud pots occur on the flanks. Two lakes, Malagsom and Danao, are located on the S flank. The former is a crater lake that is acidic and green in color, and the latter is a freshwater lake with an irregular shoreline and hot springs on its southern side. An eruption was reported in 1895, but no details are available.