Minho's tattoo
In the The Scorch Trials, each Glader was secretly Tattooed on the back of their necks with information clearly identifying them as WICKED test subjects. The tattoos were a variable to see how each individual reacted to the role they were given. Each tattoo began with "PROPERTY OF WICKED" and included each subject's group (A or B), their subject number, and in some cases their title. The title was given by WICKED based on their character, personality and illustrated the role WICKED intended for them to play. For example, Newt's title was "The Glue", meaning that Newt's personality as the level-headed center of Group A was the glue that kept the group together; it also referenced the fact that he was the control subject of Group A. As for Thomas' title, "To be killed by Group B", it was intended to foreshadow WICKED's designs. Minho's tattoo was The Leader and as such, he led them through the Scorch.
- Thomas: "To be killed by Group B" A 2
- Teresa Agnes: "The Betrayer" A 1
- Newt: "The Glue" A 5
- Minho: "The Leader" A 7
- Frypan: "The Sidekick" A 8
- Chuck: A 4
- Aris Jones: "The Partner" B 1
However, in the Films, they were supposedly replaced by the Tracking tags in the backs of the Gladers' necks. These trackers helped WCKD to locate the Gladers. They were first encountered a tracker when a WCKD soldier scanned the back of a girl's neck at the start of The Scorch Trials (when WCKD and Janson arrived at the scene when the Gladers attempt to rescue Minho). When first meeting the Gladers in the Film, Brenda used a device to scan these trackers on their necks. The first person she identified was Thomas. Jorge then went on to point out that they came from WCKD and that they were "Very, very valuable". This led to them being hung upside down in Jorge's group's hideout. We later saw the trackers in the The Death Cure, when Teresa removed the trackers from the Gladers' necks. This happened after they reunited with Teresa inside the Last City. Teresa said that if they wanted to sneak into the WCKD Complex, they'd need to remove the trackers. This was what led to Teresa removing the trackers from all the Gladers' necks at Thomas' behest. Gally remarked "She enjoyed that" as he pressed a cloth on the open wound on the back of his neck where the tracker had been removed, with Frypan, whose tracker was also removed by Teresa, in agreement. This was the last time that we see of them in the Films.