Dead Island: Riptide - Definitive Edition

Oil is oily, but still, they say that it is necessary to put up El. fences during the defense itself, this is when “Strength of the Horde” is added on top of the screen

When the “Strength of the Horde” sign comes out, you need to remove and put back five different fences, not necessarily electric ones.
The first opportunity will be when defending the ruins while the pump is running, the second when defending the ferry.