So you want to murder your Sims? Here are some fun ways they can die...
1. Starvation
Really the simplest way to kill a Sim, it's also one of the longest, most boring, and most pathetic. Just prevent your Sims from obtaining any food, either a refrigerator, coffee maker, vending machine, telephone (to call for pizza), etc. They'll complain and cry for about FOUR DAYS before they finally pass on. You can somewhat hasten their demise by forcing them to exercise, such as swimming, playing basketball, or using the weight machine, but they won't want to do these things once they start feeling bad. You can use this method to kill visiting neighbors, but not NPC's. Sims who are near death may be visited by the ghosts of other dead Sims if there is a tombstone or urn on the lot.
2. Drowning
Another simple and fortunately quick and painless way to kill your Sims, just build a pool with a diving board and no ladder. The Sims will foolishly dive into the pool, and only then will they discover there is no way out! Once their energy level reaches zero, they die immediately. The Grim Reaper will not appear. You can hasten their demise by making them eat turkey just before swimming. This method works on neighbors, but not NPC's.
3. Fire
Fire is probably the second most spectacular death, though it is somewhat more random than starvation or drowning. Placing a flammable object next to an ignition source will greatly increase the chance of a fire. Possible ignition sources include stoves operated by Sims with zero cooking points, barbeque grills, fireplaces, campfires, and model rockets. Using a model rocket indoors always results in a fire, and Sims are often stupid enough to launch them indoors. Fire can kill neighbors and NPC's who get too close.
4. Fire Storm
The absolute most spectacular way to commit mass-murder. Simply place rugs through a room, so that the rugs overlap each other. Leave one square uncovered. Then place the model rocket launcher in the room. When someone launches a rocket, it will land in that one empty square and the entire room will ignite at once. The number of flames appearing could potentially crash a slower computer, so try not to make the fire too big. Because you can easily kill a dozen or more Sims at once, it may take the Grim Reaper several minutes to collect all the dead. This will kill anything in the room, including neighbors and NPC's.
5. Electrocution
Really too random to be an effective murder tool. If a Sim with no Mechanical points attempts to repair an appliance, the result is almost always fatal. There is also a 1% chance of electrocution while changing a light bulb, regardless of Mechanical skill. This death can only affect family members, not neighbors or most NPC's. Sims can also be electrocuted if they attempt to use an electric appliance while they are standing in water. This CAN kill neighbors and NPC's.
6. Guinea Pig Disease
Again, another death that's fairly random. If you don't take proper care of the guinea pig, it may bite and infect your Sim with the dreaded Guinea Pig Disease. Unless steps are taken, the Sim will die from it. The disease apparently does not affect neighbors or NPC's. The disease starts as mild cold, with minor coughing and the occasional sneeze, gradually progressing to a major illness, and eventually death. See below for cures, if you want to save your Sims for some weird reason.
7. Woodworkers Disease
One of the rarest deaths, continuously operating the woodworking table in a room with no windows may result in a Sim becoming ill. Cures are probably similar to those for the Guinea Pig Disease. This disease probably does not affect neighbors or NPC's.
8. Spontaneous Combustion
The most extremely rare form of Sim death. I've only heard of this one, and never seen it. There is no known cause. The Sim just randomly bursts into flames. It is unknown if neighbors or NPC's can suffer from this.
9. Slurm Overdose
The Slurm Vending Machine (It's highly addictive!) is a download available on the Internet, it does not come with the Sims. It's a fairly cheap vending machine, a mere $100. However, if your Sim drinks too much Slurm, he/she will double over in pain, collapse, and die. This may affect neighbors, but probably will not affect NPC's.
Ways to Beat Death
1. Don't Fear The Reaper
Any adult Sim who is still alive can plea with the Reaper for the life of the victim. There's a roughly 50% the Grim Reaper will take pity, and challenge the Sim to a game of Rock, Paper, Scissors. If the Sim wins, the dead Sim is brought back to life. If the Sim loses, there's a 50% chance the Grim Reaper will still take pity, and revive the deceased as a zombie.
2. Cheat Death
Go into Buy Mode. Press CTRL + SHIFT + C, and a small box will appear in the upper left corner. Type "move_objects on" and press ENTER. You can then click on the Grim Reaper, and press the DELETE key. Then click on the dead Sim and press the DELETE key. Then go back into live mode. The deceased Sim's icon will still appear with the others, but with a crosshairs symbol on it. Click on the icon, and the Sim will reappear, with his health and motivations fully restored (however, he will have lost all skill points gained since the last save) This will not work for drowning (drowning deaths are instant), nor will it work if there is an active fire (can't go into Buy mode).
3. Curing the Guinea Pig Disease
There are three ways to cure this deadly disease. The first is good old R&R, Rest and Relaxation. Make sure the Sim gets plenty of sleep and food. They will eventually recover on their own. The second way to cure the disease is to buy the Concatenation Station chemistry set. Have the ill Sim keep making potions until he/she creates a White potion. This is the cure for the Guinea Pig Disease. The odds of producing a White potion are only 1 in 11. The third and most reliable way to cure this disease is to purchase the Forgotten Guinea Pig painting.
4. Cool the Burn
A nearby Sim can sometimes extinguish a burning Sim if they are quick enough.
5. Going Downtown
Sims are apparently immune to death when they go Downtown. This may also apply to Vacation Island as well. A Sim can go weeks without food in the Downtown area. They won't be very happy, but they won't die.