So at my local store/tournament scene Slaanesh and Skaven are currently running the roost. I am just curious about pulsing the community on dealing with Slaanesh lists and their ability to summmon like an extra 800 points in one turn.(exaggeration). Let me know tactics or lists you have found work. Thanks!
For Slaanesh you need to kill their heroes. They are only able to summon around their heroes. Don't fight their Keeper of Secrets with any glass cannon. The best way to kill them is with shooting or mortal wounds that are not tied to a combat action. Skaven will be torn apart by Rippers and Razordons. They are one of the top tier armies that our faction has a good match up against.
Thunderquake+Razordons all the way. Bastiladons with 3 damage are great. Use slann to create skinks screen, it should be enough to slow down their hordes/monsters for 2-3 turns, while you destroy them from afar. Stellar tempest can be devastating against their blocks, dealing 10-12 MW, considering you roll OK. Same for meteoric convocation against squishy support characters. Use them+psybolt, and will have about 3 wounds per hero phase, unsless they can ignore them. Than finish them with shooting.
Force them to fight your single wound models, to reduce the amount of summoning they can do, while blasting them with targetd EoTG mortals and solar Array Basti's. avoid letting multiple wound models get into melee combat with their heroes.