Redcap Sappers are mobs from the Twilight Forest mod. They have 30 health, 15 hearts and attack for 1 heart worth of damage. Redcap Sappers are tougher versions of their cousins, the Redcap Goblins. Redcap Sappers can only be found in the largest Hollow Hills. In addition to having more health and carrying Ironwood Pickaxes and Boots, the Redcap Sappers could also drop Primed TNT and blow you up!
Like Redcap Goblins, they also drop Coal in addition to their Ironwood Pickaxe and Boots.