A new TV spot for Deadpool 2 seems to confirm the identity of the film's previously unnamed "kid" as "Russell" - presumably Russell "Rusty" Collins, a character dating back to 1986's X-Factor #1.
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Rusty Collins, occasionally known as Firefist, has fire based powers and has been affiliated with X-Factor, the New Mutants, and X-Force.
Newsarama previously speculated that "the kid" was Rusty Collins after his appearance in the Deadpool 2's second trailer. The identities of several mutants from the film remain unconfirmed.
Deadpool 2 is due out in theaters May 25.