Difficulty: Very easy-easy
This achievement can be earned in Wall-nut Bowling or Wall-nut Bowling 2. It can easily be earned in Column Like You See 'Em by planting a Tall-nut in the first column and letting a bulk of zombies accumulate, mowing them down in a one fell swoop, once they finally break through. This will kill a lot more than just ten, easily earning you the achievement. One of the easier ways is to play Level 1-6 when both the Wall-nut and the shovel is obtained. Plant Wall-nuts as fast as possible and when reaching the "Final Wave," dig up all plants except for Wall-nuts and wait for the zombies to pile up to at least ten zombies, then dig up that Wall-nut and let the zombies clump to go to the Lawn Mower and kill them. This is an easier strategy than the mini-game ones.
You can also go to Quick Play mode and choose Level 1-1 (the level which only has the regular Zombies). Choose any plant that you like to use, but make sure you choose Sunflower, Peashooter, Tall-nut, and Imitater Tall-nut. Be sure to use the Garden Rake as it will be invaluable to you. Once the level begins, start planting Sunflowers in row one, two, three, and five. When the first zombie appears, just ignore it, as the Garden Rake will take care of it.
Once you get enough sun, plant a Peashooter in the lane where a zombie is approaching. Remember that Level 1-1 has only regular Zombies. In the empty lane, plant a Tall-nut on the first space (the point where the lawn ends on the right side of the house). Keep planting Peashooters in front of the Sunflowers. When a Zombie appears in the lane with the Tall-nut, plant an Imitater Tall-nut behind the first Tall-nut. Keep doing this, one Tall-nut after the other. Be careful, though. When the zombies start to clump together in the Tall-nut lane, an Imitater (before it turns into the plant) will be eaten with one chew from the clump. Keep planting Tall-nuts. When you think there is ten zombies, let the zombies swallow the Tall-nut(s) and watch them walk toward their death. When they reach the Lawn Mower, they will be crushed and you will get the achievement. Do not direct all of your attention toward that, though. Do not forget about the other lanes. Remember that this is not a get-this-achievement-by-end-of-level thing and is hard. If you mess up, keep trying.
Complete Level 1-1 or 1-2 using the following:
- Garlic to force all the zombies into one lane.
- Cherry Bomb or Coffee Bean and Doom-shroom in case of an urgent need.
- Other offensive plants you deem necessary
Go through the level as you usually would. Sometime during the level, plant Garlic in every row except one (you may need to plant several columns to force every last zombie into one lane). Then, on the final wave, use the shovel to get rid of every plant in the row that does not have Garlic, then let the Lawn Mower defeat the entire horde. If some were left out, use a Cherry Bomb or Doom-shroom with Coffee Bean to get rid of them.
- Pool Cleaners and Roof Cleaners can also be used for this achievement, despite the name and the description of this achievement.