I tried these so you don't have to. Spectres use earthquake on 12 sec cd with 50% phys to lightning conversion, which can be used with multistrike. Performance with 9 of them is beyond terrible even on absolute lowest graphic settings.

Here is PoB for those who like to torture them self:

https://pobb.in/JwvSH3rkqoW7

https://poedb.tw/us/Electric_Executor

Get them from T17 maps or by taking Invasive Adversaries node on Atlas tree, then spam low level maps and just use desecrate.

This was recorded on standart league.