German sappers were jacks-of-all-trades. They cleared enemy barriers, and overcame natural obstacles. During the assault of enemy fortified positions, pioneers cleared a path through wire entanglements and minefields. Sappers often had to set out as strike forces: lay landmines under the defensive units or drive the enemy out using flamethrowers. In defense conditions assault pioneers constructed military defense installations involving trenches, wire entanglements, placed minefields.