Rigellians

Rigellians
Rigellians were an enemy that the player had to tap during the Treehouse of Horror XXV Event. The Rigellians only appeared in a player's town after Pt. 4 of the Free Hugs questline, and after building the Weapon to actually be able to tap and kill them. Once this was done, the Rigellians began to spawn in the players Springfield, and in Neighbor Springfields.

When the Rigellains were tapped on in the player's own Springfield, they yielded three of the current currency in the game, (Probes from October 7th - October 19th, Ray Guns from October 20th - October 30th, and Protein Strands from October 31st - November 12th). Rigellians also had a small chance at spawning Ammo and Treat Bags. Rigellians spawned in a player's town at a rate of 1 every 5 minutes with a max at 80 Rigellians. (50 will be visible, and as they are tapped, the remaining 30 will spawn).

When in friend's towns, the players had a limit of 90 friend Rigellian interaction per day. Each Rigellian squished in a friend's town yielded one of the current currency. Once the limit was reached for the day, no more Rigellians could be squished until the next day.

If the player purchased the Rigellian Hunting Licence for 100 Donuts, it increased the amount of currency that the Rigellians yielded in friends's towns from one to two, so if all actions were completed, it double the amount of currency the player obtained from friend's towns. This did not affect the amount yielded in their own towns.

Grem-Aliens
Another type of Rigellians were the Grem-Aliens, could be placed by a player in their friend's towns using Grem-Alien Eggs. Grem-Alien eggs were obtained from tapping Rigellians, or from buying them in the store.

Grem-Aliens could be placed in Neighbor's towns, but could only be tapped in the own player's towns. When tapped, if it was not tapped within four hours of being placed in the player's Springfield, the other player earned a reward. If it was tapped, the reward was shared. US$