This quest is all about building mean relationship and it is only good for 1 week for you to complete. The main objective of this quest is to have a rivalry with other Sims. It has 5 stages and each stage has three task to accomplished. You'll get certain number of Simoleons as a reward by completing each stage.
First Stage - How to Complete
Make a Confrontational Introduction
Talk to a Stranger Sim. Select the mean introduction which is "Make Confrontational Introduction".
Make a Big Stink
Once your relationship status with another Sim change to "Acquaintance", Tap on it and select this mean interaction "Suggest deodorant". You can select any Sim as long as they are "Acquaintance" with your Sim.
To start this Social event "Become Icy Acquaintances", your Acquaintance Sim should be at least level 2. To complete the event, you must perform actions to fill the progress bar. You can speed up your progress by performing risky actions. Just make sure your Sim has enough confidence to increase the chances of successful risky actions.
Second Stage - How to Complete
Complete 1 Risky Action in a Hobby
Tap on your Sim's hobby object and start a Hobby event. Perform event actions and wait to have your Sim gathered enough confidence. Once you receive a notification about Risky Action and you still have enough energy left, perform it. It doesn't necessitate you to be successful. You just need to execute it.
Be Really Irritating
To tick this task out of your list, your relationship status with a certain Sim should be "Rival". Tap on that Sim and annoy it. Select "Rankle relationship" to fill this task.
Frenemies are your foes disguise as your ally. The main goal of this task is to level up your competing relationship with your "Rival" Sim. This time you'll turn "Enemies". You can initiate this Social event once you've met the appropriate Relationship level which is Level 4. Perform and complete the event to conclude the this task.
Third Stage - How To Complete
Complete 1 Risky Action in a Career Event
This task is also similar to the Risk Action task in the previous stage, only this time, it will be Risk Action in a Career Event. Simply perform a Career Event, perform and wait for your Sim to notify you about the Risk Action. Make sure your Sim has enough confidence to make this Risk Action successful or else, you'll flunk. Whatever the result is, this will surely complete the job.
"Jab" your enemy
You don't need to punch your Enemy Sim literally. This interaction is simply to annoy your Enemy. You just have to tap on your Enemy Sim and perform "Jab raw scorn into ego" to complete this job.
Become Sworn Enemies
Sworn Enemies are your foe you think unforgivable until the end of time. In this task, your Enemy Sim should be at least Level 6 to perform this Social Event. As usual, you just need to execute actions and fill the event's progress bar. Completing this event will surely step up your mean relationship and conclude this task at this phase.
Fourth Stage - How to Complete
Crush Hopes and Dreams
This task is just a simple interaction with your sworn enemy. All you have to do is tap on your sworn enemy and select this said interaction. This will cost you 1 energy and you'll be rewarded with 10 Relationship XP.
Complete 1 Risk Action in a Social Event
Initiate any social event with anyone in your home. Perform actions in the event and try to acquire enough confidence. Once Risk Action is available in the option, tap on it and execute. The end result is not what's important. The main goal is just to perform it. Complete the event and move to the next task.
Nemesis is your long-stand rival. Just like Harry Potter's foe Voldemort, he/she can be evil as a demon. This relationship status can only be attained once you've reached "Sworn Enemy" status with another Sim and it should be at least Level 8. Simply start and complete the social event "To Become Nemeses" to conclude this task.
Final Stage - How to Complete
Complete 5 Risky Actions
This task is quite easy to fulfill. You can complete the task by starting two events. Any type of events will do. In a single event, you can perform at least 3-4 Risk Action. Try to complete each event for a better reward.
Discuss Reciprocal Disgust
"Discuss Reciprocal Disgust" is just a plain interaction between you and your Nemeses. By simply tapping your Nemesis and choose this said interaction will conclude this task. The action will only last for a few seconds, but will cost you 1 Energy. You'll get 10 Relationship XP after.
Become Arch Nemeses
This is the final task in this quest. This is not a difficult task to do as long as you have your Nemesis with you. If none, you have to start building this kind of relationship again. Your Relationship Level with your Nemesis Sim should be at least level 10 for you to start this mean social event. Once you've finished the "Become Arch Nemeses" event, that will also complete this task as well as this quest.