Arbiter_Shade wrote:
If you want any kind of synergy or bonuses just play mono god, you lose most of the benefits of a detachment when you mix gods. Your infantry are arguably more squishy than boyz so be prepared to field large blobs of infantry in order to get them to survive more than a turn.

If you do go dual god you just need to make sure that you use multiple detachments to keep the bonuses. The bonuses you do get are also tied to HQ characters so it pays to have at least one or two small HQs in order to spread those buffs out.

Slaanesh can be very overwhelming if you build your list right, you can get across the table in a turn and be assaulting your opponent turn 1. I play Slaanesh and while they CAN be scary against an opponent who knows what to expect they are easy to counter. Khorne is just...kinda bad at everything. Some units are decently scary when you get them in but because of the edition shift a good bit of their melee power is worse than some other new codexs basic infantry. Tzeentch can be a problem for some opponents just because you are a huge psychic presence and that can skew the game if they don't have a way to handle it. A lot of the Tzeentch attack powers are straight up worse than smite but when you pile them all together you can do some serious mortal wounds. Nurgle is SUPPOSED to be super resilient right? Well Plague Bearers are T3 5++/5+++ which is NOT very durable in terms of the current meta. A GUO is T7 5++/5+++ which can be improved by making them a Greater GUO but it is still kind of sad how squishy they are.

Summoning is awful and you may as well forget it is even a rule. I wish I could say otherwise but it is a super rule heavy version of standard deep strike that requires you to use a character that can't do anything else BUT summon on that turn.