Spikerock is a plant in Plants vs. Zombies. He does double the damage of a normal Spikeweed and can be punctured/smashed up to nine times. He is a passive attacking plant, dealing high damage to any zombie that walks on him.
He usually deals five attacks to every normal speed zombie that passes unimpeded over him (exceptions include zombies that come in a group, when one zombie gets on just after the Spikerock fires). Since the Spikerock attacks from below, he bypasses shields.
Spikerocks will pop tires, up to a different number of vehicles before dying in different games, with one of his large spikes breaking off with every one-third of health. When a Gargantuar attacks him, he will have the same effect as when vehicles roll over him, hurting the Gargantuar.
Spikerock is the upgrade of Spikeweed, and is purchased from Crazy Dave's Twiddydinkies for $7500. He costs 125 sun to upgrade a Spikeweed to a Spikerock, for a total cost of 225 sun. Spikerock absorbs nine smashes and his appearance changes at the third and sixth smash before finally being dead at the ninth. He loses one of his large spikes when smashed three times. He will damage zombies at ten health of damage per a regular zombie's patch speed. He will automatically kill Zombonis and Catapult Zombies by popping their tires.
Suburban Almanac entry
Spikerock
Spikerocks pop multiple tires and damage zombies that walk over it.
Must be planted on spikeweeds
Spikerock just got back from a trip to Europe. He had a great time, met some wonderful people, really broadened his horizons. He never knew they made museums so big, or put so many paintings in them. That was a big surprise for him.
Cost: 125
Recharge: very slow
Strategies
Using slowing plants like Snow Pea or Winter Melon can provide a great damage increase to ones Spikerocks, because zombies will be walking over them for twice the amount of time. Kernel-pult can also be a good option because of his stun.
Planting defensive plants behind Spikerock is another good idea, as zombies will stop to eat the defensive plant while taking damage from the Spikerock.
Spikerock is uniquely capable of withstanding multiple strikes from Gargantuars. This considerably slows Gargantuars and allows extra time for your other defenses to attack, since, unlike other zombies, Gargantuars will stop to destroy Spikerocks.
As he can pop multiple tires, Spikerock is an incredibly useful plant to use in the mini-gameBobsled Bonanza. It is a good idea to plant a column of Spikeweeds at the edge of the ice to deal with Zombonis, but they should be upgraded to Spikerocks as soon as possible. To deal with the Zombie Bobsled Teams, there should be an additional Spikeweed behind the Spikerock (as the zombies can only take one normal damage shot after passing over the Spikerock, although when first setting up it is best to plant three).
Survival Mode
Though useful on the early waves, Spikerock is not recommended for Survival: Endless due to overlapping Zombonis, Catapult Zombies, and assorted Gargantuars. Often, a Spikerock may be killed shortly after he was placed down. However, Spikerock is ideal for any normal Survival Mode level, easy or hard. The ability to kill multiple Zombonis, that if left alone, will crush your setup, is a superb one by any fact. He can also save your offensive plants some time, as one Spikerock can kill a Basic Zombie without help. Many strategies use Spikerocks planted on the back most column in Survival: Endless to kill Digger Zombies.
Of these, only Jack-in-the-Box Zombies, Bungee Zombies, and Jalapeno Zombies are capable of destroying a Spikerock in one attack.
When he is planted in one of the two bottom right squares, he will be higher up than other Spikerocks. This is so the player can see them over the level progress bar.
He is the most durable plant in the game, because he can withstand nine Gargantuar's smashes and nine tire pops of the Zomboni and Catapult Zombie. Despite his resilience, he still only takes take one Jack-in-the-Box Zombie or Jalapeno Zombie explosion or Bungee Zombie grab to destroy a healthy Spikerock.
Jalapeno Zombie cannot destroy something biologically rock, as his melting point would be massive and take temperatures vastly beyond the output of a Jalapeno Zombie, and the fact that rock is not flammable makes the very brief blast of the Jalapeno Zombie seem even less able to destroy or melt rock.
He can still harm Bungee Zombies, despite them being an airborne zombie.
He is one of three plants that have names which do not involve plants, with the others being the Grave Buster and Gold Magnet.
He is one of only two plants that change appearance but cannot be healed with Wall-nut First Aid, the other being Garlic.
He and Squash are the only plants that can survive Gargantuar smashes and a vehicle running over them.
He is the only upgrade plant that cannot be eaten.
On the iOS and Android versions, He does not visually degrade, making it harder to tell if a Spikerock is weak or not.
Spikeweed, Spikerock, Cattail, Grave Buster, Tangle Kelp, Sea-shroom, and Lily Pad are the only plants that cannot be planted on a Flower Pot.
The Almanac entry of Cob Cannon, Garlic, and Spikerock are the only ones where real world places are mentioned (Harvard, New York, the Uni Brüssel, and Europe).
Despite being an upgrade to Spikeweed, he is not an actual plant, as rocks are not living organisms.
