Ever since you play PvZH, you need to know many of the common decks. I can help with the Zombie side since I am a Zombie main.
- Pet decks focus on setup. First off they setup using Cat Lady or Zookeeper, then they rush. Their Pros is that they go bananas when you use them properly. Their Cons is that you must setup before spamming and in late games the setup will be broken due to cards like Sizzle and Banana Launcher screwing you up. They are commonly Zoo decks. Brain Freeze mostly specializes this deck.
- Science decks focus on a mix of everything. Conjure, Transform, Grow Strong, Bonus Attack. They could do anything literally. In fact there are many good Science cards like Z.D.E., Gadget Scientist, Zombots, everything. Their Pros is that they have many ways of confusing the opponent. The Cons is that if the Plants know what you are using, they know how to counter you easily and don't forget that many Science cards trade their stats for the mix of everything. They are commonly RNGezus decks. Every Brainy hero specializes this deck.
- Dancing decks focus on swarming left and right. Once they swarm, they prepare for something strong. They play aggressive and troll the heroes a lot. Their Pros is that they are known to swarm everywhere. Their Cons is the worst, as they swarm, you drain your hand, they can't deal bigger threats like Soul Patch and they need to be played very aggressivly or else they miss the beat easily. They are commonly Aggro decks. Dancing decks aren't that common because of how their Cons are so bad.
- Sports decks focus on wrecking mayhem. By simply getting out of control if taken well. These monsters are strong due to this. Their Pros is that they're easy to obtain as well as being powerful later on. Their Cons is that these monsters have expensive costs (though this isn't a con because of Flag Zombies and Cosmic S.S.), however they die instantly by Doom-Shroom and yet once you play them, your opponent may play something to counter them like Squash or Berry Blast. They are commonly Control decks. Rustbolt mostly specializes this deck.
- Imp decks has a complicated stratagy. As they're a combination of Dancing, Pet and Science. They can rush, setup and have a mix of everything. They rush quickly, they have setup like Imp Commander and they can mix between either Anti-Hero or conjure. Their Pros is that they are a mix of three said tribes and they are dangerous if mastered. Their Cons is that it takes a lot of practice to master Imp decks and they can easily be wiped out by the likes of Kernel Corn. They are commonly Zoo, Aggro or Face decks. Impfinity mostly specializes this deck.
- Pirate decks were made to directly hit the Plant hero. WIth Anti-Hero and Swashbuckler. The Plant Hero would usually have many ways to counter this deck. They also ran Buried Treasure for conjuring madness and Unthawed Viking for freezing dangerous plants like D.M.D. Their Pros is that they gain huge benefits from directly hitting the plant hero. Their Cons is that if the Plants are careful, your setup plans are ruined. They are commonly Midrange, Zoo or Face decks but can also be Combo decks. Impfinity mostly specializes this deck.
- Professional decks is the same concepts of Pet decks. They must set up with Zombie Middle Manager and then swarm. Jurrasic Fossil Heads are also an option as well. Their Pros and Cons are the same as the Pet decks. They are commonly Zoo decks. Every Hearty hero mostly use this deck but Z-Mech uses them quite commonly.
- Mustache decks can be treated as Science decks however they trade most of them for stat boosts. Their Pros and Cons are the same as Science decks. They are commonly Ramp or RNGezus decks. Super Brainz and Huge Giganticus mostly uses this deck.