After the initial release, alot of people could see the rules were unclear at points or some things very unbalanced.
All changes were made towards clarification and balancing.
You do not "need" the cards, you can always use the Force Index for stats (1 page for all the Faction's minis).
Basic card changes, in a nutshell:
LD is gone
CC Weapon STRENGTH is now a modifier to model's strength (all kept the same total as before, apart from specific models)
Abilities which occure due to a weapon are now clarified more (you can also see it from the Force Index)
All aliens get a special cc extended action: make a normal attack and add 1 extra die which hits on a +1 strength.
All aliens explode on 1-6
Warrior, Royal Guard, Queen, Crusher have been nurfed/buffed.
Warrior Hero (40mm) and Royal Guard Hero "added"
Smart Disc Nurf
Youngbloods Nurf and Equipment Change
If you use the old stat cards, you should check and compare every one of them with the stat line, and definately read the abilities from the rulebook.
Event cards do not have any important changes
Strategy Cards have just been clarified. Tactical Advantage should be played a bit differently:
1. does not count towards limit of cards/turn
2. place it in your discard pile, draw 5 and discard down to 5
3. resuffle discard into deck
So, long story short:
Rules 2.0 (download the WiP rules from avp.prodosgames.com/downloads) combined with the errata found in the official facebook page (https://www.facebook.com/groups/AvP.Prodos.Games.Official/fi...
) are the way to go.
The seccond edition rules are as Gary pointed out, essentially the same game corrected and balanced.
You have no need for the new cards, you can make the adjustments yourself (if you use stat cards).
So far, judging from the comments, I have seen alot of people stating that they like 2.0. I hope you join the ranks