Catapult Zombie will be difficult without using any instant kills or Kernel-pults. One should use Squash or Potato Mine to destroy it. It is a bad idea to place a plant (except instant-kills other than Chomper) on tiles where the Catapult Zombie is as its vehicle has the ability to crush plants regardless if it is moving like the Zomboni or in idle animation to lob basketballs, and the vehicle's crush radius can range from 1-4 depending on the Catapult Zombie's position when it is idle and how many plants are on the tiles they occupy before the zombie occupies them. Planting on tiles where the Catapult Zombie will later occupy is also not a good idea as they will be crushed when the zombie enters the lawn due to the reasons mentioned before.
Since no Bungee Zombies show up stealing the player's plants, three Bungee Zombies will drop zombies during the final wave. Since they will place zombies on the player's lanes, they must destroy them as soon as possible.
In the Nintendo DS version, the Catapult Zombie will start moving close to the player's house after it fires fewer basketballs. Unlike in the mobile, PC and console versions, the player must be fast and have good defenses so that the Catapult Zombie will not crush their plants.
Do not place Kernel-pults in the back lanes because the Catapult Zombie will launch basketballs to deal damage and the plant will be destroyed. In addition, the Pumpkin is also useless when the Kernel-pult is inside because the Kernel-pult gets damaged before the Pumpkin.
When a Catapult Zombie shows up, avoid letting it stay too long. If the Catapult Zombie is not killed, it will start moving and crushing your plants. In the Nintendo DS version, you must be fast because the Catapult Zombie will move after it has fired fewer basketballs. Use a Cherry Bomb or any other instant-kill plants (except the Doom-shroom).
Only plant Kernel-pults and Cabbage-pults on the third and fourth lanes.
Plant Fume-shrooms and Wall-nuts on the flat top of the roof on the seventh lanes only. Never use Garlic, because these zombies will deal more damage to your Wall-nuts. If you want stronger defenses, plant Tall-nuts instead.
When the ambush zombies are dropped, plant a Squash near your Fume-shrooms if one of them has landed on your Fume-shrooms. This will save them from being eaten by the zombies dropped by the Bungee Zombies.
If possible, plant Wall-nuts or Tall-nuts in the back column to ensure the catapult zombie will not hit any other plants.
Strategy 2: An Alternate Smell
Required plants:
Sunflower
Flower Pot
Cabbage-pult
Repeater
Coffee Bean
Fume-shroom
Gloom-shroom
Garlic
(9th Seed Slot) Cherry Bomb
(10th Seed Slot) Jalapeno
This strategy starts similar to my strategy of Gloom-shroom Crush, with the Sunflowers and the rake and everything. However, the SECOND you would build the barrier, the strategy changes. Now you place Gloom-shrooms on rows 2 and 4, and put Garlics in front of them. In the lanes that the Garlics send zombies to, put Repeaters on column 5. Behind there, everything is the same.
I had to keep some Fume-shrooms too, in order to defeat Catapult Zombies
First wave
Here they come...
Final wave. The Pumpkins should protect the Gloom-shroom from zombies dropped by Bungee Zombies. I also used Squash on the Catapult Zombie to end the level faster.
Completed. With this strategy, I also earned the Grounded achievement.