Last review I did it was about gw1 and it's pretty good 8/10 but I don't recommend buying it because this game is that but better.

Anyways I wasn't really sure where to start off with this so I'll just say the stuff they added into this game
-Graveyard ops: It's garden ops from the last game but with zombies defending this time which is nice and gardens ops is also back
-6 New Characters: All the old characters are back and now including Imp, Super Brainz, Captainbeard, Rose, Corn, and Citron all of which also came with variants and all the old characters also got new ones which was pretty nice and kept gameplay fresh you could say. (I would also like to point out now that new variants were added with each update and 2 new classes in another update, those classes being Torchwood and Hover goat 3000 but those never got any variants.)
-A story mode for both plants and zombies, new maps, new cosmetics, golden gnomes which I won't talk about, the town hall (a place were new game modes would take place which would give you rainbow stars which were used to open chest and my god this game was big lets move on) 
Probably the biggest change was the introduction of the "Backyard Battleground". Instead of being put in a menu screen when you open the game, you're put into a pve region with 2 sides (plants and zombies ofc) where you could *ahem* upgrade characters, do the story mode, explore, open chest, find secrets, do the flag of power, fight ai or friends, AAAAAAAAAAAAAAA.
Like I said this game was the last one but much much bigger and it's probably the most played pvz game today despite it no longer getting new updates but still getting supported in a way. 
The only problem I have with the game is with some of the variants and some of the legendary variants as well. I won't really mention them but people that know which characters I'm talking about then you know how I feel about them. Some of them is what we call "bull shit" and you could even buy some of the legendry characters with real money you know because EA. Do keep in mind this game has over 100+ variants  so trying to balance ALL of them is very difficult which causes more problems. Also because this is a multiplier and a shooter game you will experience some bs but that can't really be helped so I won't really count that against the game. Oh and the game has way too many cosmetics mainly because of the different versions of the cosmetics you can get (sliver, gold, diamond, blah blah blah) 
Anyways I did miss out on some stuff because this game is just really big but I do recommend you buy gw2 because it is pretty good and at least better than gw1. My final rating would be 9/10 and let me know about how you feel about this game. That's it bye have a good one