They can be scared by throwning objects such as stones at them or by sending out the creature to scare them away. Fire will not work, as they will be immediately put out as soon as they start to burn (presumably due to the permanent storm overhead, maintained by the Guardian Stone that Sleg is guarding).
After Sleg is defeated, they will stop the raids and stay by their hideout. These ogres become humans upon death.
- Additionally to keep the ogres at bay you can build an improvised wall out of whatever you can find (Rocks, fences etc.) any material big enough for them not to cross around your village with a gap for your creature to get through and guard when he is not needed (may want to put field nearby so he doesn't starve but its your choice).
- It is possible to get NPC creatures with similar behaviours on community-made maps.
- Arguably the best solution is to raise the village totem to 100%, which will leave no villagers for the gremlins to grab, causing them leave without attacking anyone.