"Agent Citron has just located one of the most wanted bounties. Track him down and claim the bounty."
Agent Citron reveals that he has managed to find the location of an important bounty, and instructs the player to seek out Ironball, an Iron Citron, to help capture the bounty. However, Ironball is trapped, and the player must get the key to his cage. After freeing Ironball, the player will then have to proceed to the docks to vanquish a S.H.R.IMP in his mech. After defeating him, Ironball will speak to the player briefly, after which the quest is completed and the player receives their reward.
Ironball can be found in an area behind the Town Hall, trapped in a cage. Along the way, the player will encounter some Browncoat Zombies and Conehead Zombies, which should not be too big of a problem.
To obtain the key to free Ironball, the player must vanquish a Champion Robo-Zombie. This Robo-Zombie will drop the key to Ironball's cage. After this, the player will then proceed to the docks. It is worth noting that Ironball will not go into ball form, so the player has to match the slow speed of the Iron Citron. Some Browncoats and Future Imps will also spawn in the path.
The S.H.R.IMP will be fought on the bridges on the docks. It is not advisable to go onto the platforms to engage him, as his abilities can easily knock the player off, vanquishing them easily. Instead, the player can simply shoot the mech from the side.
Citron variants are the best for this mission, as they can cripple the S.H.R.IMP very badly with the EMPeach. However, any plant class with a high damage output like Kernel Corn will work for this mission.