Some Pokemon will be out and about in the streets employing scare tactics to hapless trick-or-treaters, as "Pokemon Go" gets a Halloween update, which includes some of the spookiest and naughtiest Pokemon.

For this week and the next, players will be able to partake in developer Niantic's update for Pokemon Go. The Halloween promotion includes special bonuses and additional Pokemon to catch and fight. These new Pokemon will be taken directly from the original game's third generation (Gen 3) of pocket monsters. The said new classic Pokemon will be added sometime between Oct. 20 and Nov. 2.

Along with Gen 3 additions, Pokemon from the first and second generation are also to be added. So far, the list includes Ghost-type Sableye, Shuppet, Ghost-type Banette, Ghost-type Mega Banette, Ghost-type Duskull, Ghost-type Dusclops, Ghost-type Ghastly, Ghost-type Haunter, Ghost-type Gengar, and Ghost-type Misdreavus.

Reports indicate that the added Ghost and Dark-type Pokemon are easier to spot at night since their chances of spawning are increased by 50 percent, but that does not mean they are scarce during the day. There will also be plenty of opportunities to catch one in broad daylight.

In addition to the Ghost and Dark-type Gen 1, 2, and 3 Pokemon, Shiny versions of Gen 3 Pokemon are also available for capture. So far, there have been reports of a Shiny Sableye hatching from a 10-kilometer (km) egg.

It is not yet certain whether these new Ghost, Dark, and Shiny Pokemon will stay around after the Halloween or not, so players are advised to make the most of the event as there is a chance that they may get pulled out.

Still, players need not worry as Niantic will also supposedly be releasing a big list of Gen 3 Pokemon in December, though the rollout would be gradual. This could mean that there may be more big events to be introduced in the coming months. Pokemon trainers are advised to stay tuned for Niantic's further announcements.

The Halloween event for "Pokemon Go" lasts until Nov. 2.