Thrax is cocky, and will often neglect the technology given to him. However, he will follow orders, and shows the usual Irken cruelty.
Thrax has red eyes, regular male antenae, a red unform with a tail like Tak's, red gloves and boots, and red spots on his PAK. He also has an implant on the right corner of his head which Vax gave him.
- Invader Vax-Vax trained Thrax. They've been friends. Always will be.
- Invader Vex-Vex supplies him with advanced weaponry. They are good friends.
- Zim-He hates Zim for killing Miyuki, for Thrax was born from the same batch as her and they were good friends.
- LIRK-LIRK is Thrax's SIR Unit which he and Vax built since they turned down his request of Mep being given to Thrax. LIRK is very loyal to Thrax. They are good friends.
- Mep-Thrax wanted to be Mep's master, but Vax's request for Mep to be given to Thrax was rejected, causing Thrax to develop a hatred for the creators of the JEVI Units. Thrax and Mep do not often interact, but when they do, they don't get along too well.