Tomas approaches the Courier after getting into a gunfight with Jacklyn who had been his traveling companion. It is implied that Jacklyn attacks him for his "Lucky Necklace" which turns out to be made of 7 Sunset Sarsaparilla star bottle caps. Alternatively, Jacklyn may actually win the fight and run over to you, saying how Tomas tried to kill her. She will have all nine Sunset Sarsaparilla star bottle caps on her (the 2 she had initially and the seven from Tomas's necklace). Which ever one dies can be found dead on the left side of the end of the road.
The Star Showdown: If he survives, he will rush over to the Courier. He will tell the Courier about his lucky necklace containing the Sunset Sarsaparilla bottle caps, and the Courier can obtain the bottle caps in a variety of ways.
A Speech challenge may be passed (Speech 50) in which he is convinced the bottle caps are bad luck, and gives them to the courier. Tomas may also be killed or pickpocketed for them, and looted for a low grade weapon and armor, as well as "Tomas's journal". Failing the speech challenge and demanding the necklace will result in Tomas turning hostile, giving the player free rein to take him down.
If he survives the fight with Jacklyn and the confrontation with the Courier, Tomas will try to reach the Mojave Outpost. Once there he will disappear from the game.
If the Courier enters Nipton from an unconventional way, such as jumping over the rocky area at the rear of city hall, Tomas may take notice of the Courier, enter Nipton, walk up to the Courier and begin his initial conversation, even though the Courier did not witness his fight with Jacklyn. This may happen both inside or outside buildings.