A Lava-Boy in Mount Pyre uses LavaBreath on Kid.
LavaBreath is a Red Enemy Tech used by Lava-Boy in Chrono Cross. First encountered inside Mount Pyre when Serge chases the Acacia Dragoons at the request of Kid, this tech is performed by Lava-Boy several times in battle and appears to be their only tech. Even Red Innates, such as Greco, suffer the same amount of damage from this tech as other Innates, when they would typically resist the damage of such techs.
Lava-Boy kicks off the ground and suspends above the target, flapping its wings. Opening its molten mouth, it exhales a fountain of steaming lava all over a single target, who glows red from the blaze.
Constructed of lava, it is no surprise that these creatures would breathe lava as well, nor is it surprising that they might exploit it to cause damage to opponents.