>>95962821 (OP)A ten man brick of Scarab occult (probably with a character) is a very expensive unit pointswise, and World Eaters have several good ways to handle it. The most obvious way are forgefiends. Triple plasma forgefiends are basically tailormade to annihilate terminator bricks, and either just keeping one hidden or sticking one or two in strategic reserves and then bringing them in as a response to the scarab occult will kill most of the brick. Another efficient way to do it are Eightbound in Berzerker Warband. They're D2, which isn't optimal, but they hit S10 on the charge which means you're wounding SOTs on 3s even through their -1 to wound, and even small units of eightbound should put serious dents into the SOTs on the charge, and they can easily be kept hidden in small terrain pieces while being fast enough to threaten large areas of the board.
So what you want to look for are things that are either S10 or D3, preferably both (forgefiends) and then find a way to deliver that damage into the brick when it appears.