It seems kind streaky. Empire, Scion and Outlander all occasionally have the numbers to take all their enemies items. Fortress does as well, and probably more often than those other three. Outlander probably gets raided the least by Scion/Empire/Trib just because nobody's ever sure how many of them are around. And because if Fortress and Empire/Scion both have numbers, then usually Empire/Scion is too busy fighting Fortress to bother with anything else. Battle is in the dumps. No idea about nexus. Trib is kind of in the dumps too.