Door of Life And Death

When most Sims hear that the Reaper is coming they want to run away, but the Door of Life and Death lets your Sim go right up and knock on his door. And you might just find that he’s not that bad after all! Want to bring a lost loved one back? Just knock at the Reaper’s door to have them reincarnated! Have a loner that wants to try parenting all on their own? Have old Grimmy Simulate a Genetic Merger with the Sim of your choosing! You can even challenge the Reaper to a high stakes guitar duel! The Door of Life And Death is an item on The Sims 3 Store. Placing it on any building allows the player to summon the Grim Reaper, providing a number of interesting interactions (see below).

Using the Door
The Door can be placed on any lot of any type, including the player's property. Use of the Door will summon the Reaper almost immediately. In order to summon him for direct interaction, the Sim must "Call the Reaper", after which he will answer and can be interacted with like an ordinary Sim. Summoning him in this manner comes with a certain degree of risk, however, as there is a chance the Sim will be pulled under the doormat by a "Pit Monster", and will be killed immediately (the ghost will be of a drowned Sim). If he is summoned for another purpose, such as reincarnating a Sim or to perform a genetic merger, this is far less likely to happen, although in that case the Reaper will simply perform the requested action and disappear.

Reincarnating Sims
The Door can be used as a means to revive a deceased Sim, in this case through reincarnation. In order to do this, the Sim must have the deceased's Sim's grave in their inventory, click on the Door, and select Reincarnate Sim. The Reaper will always revive the deceased Sim, but depending on his relationship with the Sim who made the request, it is possible the Sim will be revived as a kitten or puppy. The only way to reverse this is to kill the newly reincarnated Sim and try again, or reload a previous save. If the reincarnation is successful, however, the Sim will be revived with a completely random appearance and gender, with all familail and other relationships, Lifetime Happiness points, Lifetime rewards, and memories erased, effectively in the same state they were in at birth in their previous life. They will, however, retain two of their original Traits, as well as their name, and any skills that were acquired in their past life.

Despite lacking in appeal compared to other methods of reviving a Sim, this method can be used to change a Sim's gender, skin tone, and remove them from any family trees, as well as revert Sims to life stages earlier than Young Adult, all of which are normally impossible without the use of cheats. Assuming you can always keep a Sim with a good relationship with the Reaper in the household, the Door can be used as a single means of making a Sim effectively immortal, as Sims can be reincarnated any number of times, regardless of the cause of death.

Genetic Merger
Another use of the Door is to create a baby with any other Sim the current one is acquainted with. This is similar to another method in The Sims 3: Into the Future, but has major differences, most significantly being that in this case the offspring must be an occult of the player's choosing. Requesting this option will result in the Sim (regardless of gender) undergoing a "Cryptic Pregnancy", gaining a respective moodlet which comes in two stages, each lasting fifteen hours for a total of thirty hours of pregnancy. After this the resulting Sim will be born and develop in exactly the same way as a normal Sim.

Guitar Duel
Lastly, the Door can be used to challenge the Grim Reaper to a guitar duel, if the Sim is Level 4 or higher in that skill. Doing so will cause the Grim Reaper to appear with a skeletal guitar in hand, and a musical battle between him and the Sim will proceed. There are no apparent rewards if the Sim wins, however if they lose, they will be attacked and possibly killed by the Pit Monster living under the Reaper's doormat.

Trivia

 * This version of the Grim Reaper seems to be a separate NPC from the one that appears when a Sim dies, as his voice is that of a normal Sim and he can be seen with an ordinary appearance if he changes clothes while hanging around with the player.
 * The Door may be a reference to the Tombstone of L and D from The Sims 2, as it is also capable of summoning the Grim Reaper and reviving/killing Sims.