What is the best delta pokemon excluding starters
Considering the lack of detail, can I assume you mean attacker? The following are my favorite attackers: Mega Metagross (ruin), Scyther, Aggron, Golurk, Volcarona, Regice, Chandelure, and Regirock.
Volcarona is a fucking nuke beast
Volcarona.
Volcarona is surely great, but prankster amoongus and intoxicate hydreigon are also great. I don’t know what’s with this volcarona hype, maybe because it has no weakness but some others are great as well.
Is the wiki the only place to find the base stats of the deltas?
They are the same as their normal counterparts.
Any!
What type are they?
Haxorus or Volcarona
Prankster Amoonguss is a really good delta.
some arent avalible like haxouros and delta snivy I wanna see thier ability and moveset too XD
They are available. The only non available delta is the karrablast line.
Oh sorry for the mixup like the data on the wiki
Where can we see the level ups and abilities of all the deltas? The wiki has a lot of non-existent page links… I’m trying to plan a team for E4 and that would be super helpful!
I’m afraid I can’t help with abilities and movesets. I just know their locations but I haven’t bothered to capture most of them since it’s such a pain. I can send you a breeding reject haxorus to test for yourself tho. Please tell me how it goes. PM me your trade name whenever and we can set up a time for the trade.
Haxorus
What is Intoxicate? I can’t seem to find it online anywhere; I assume that is a new ability. Is delta Hydreigon good even without its mega? Most of the discussions of the new pokemon seem to focus on the megas.
Also, what makes Prankster Amoonguss so good, as two of you mentioned? Is Prankster its only ability, or a hidden ability? Which moves are good on it, that it learns? The wiki doesn’t have info on these, and I’m hungry for it. 
Delta hyderigon doesn’t even have a mega.