Where does such a problem come from?

Question

Blender

I'm making a sword and there must have been a bug when creating the tip. I left the edit mode to look at the model and then some kind of krakozyabra happened. What is it and how to fix it?

Answer 1

Judging by the picture, you intentionally or accidentally created duplicates of the polygons of your sword. To fix this more or less automatically - try the following:
1. select the sword
2. go into edit mode
3. go into vertex mode
4. select all vertices
5. RMB in the edit window and select Merge Vertices -> by distance.
6. A control will appear in the lower left corner of the editing window Merge by distance(as in the picture), play with the Merge distance parameter in it. The larger this parameter, the more distant points from each other will be merged into one.

PS: if the result is not perfect, then I think it will be easier to redraw your sword.