In February 2274, the crews of the USS Enterprise and USS Venture were captured at the Hus-24 drydock. Male Starfleet personnel were put to work in a tritanium mine guarded by Ubo and others. When fellow guard Lubo was attacked by Venture Lieutenant Tulb, Glynko took aim with his phaser. Ubo warned him not to fire because he might hit Lubo. Glynko fired anyway, accidentally killing Lubo. Tulb returned fire with Lubo's phaser rifle, killing Glynko with a single shot.
Ubo was frightened and ran. Kirk spotted Ubo and ordered Tulb to shoot him before he could warn other guards. But Tulb was unwilling shoot the fleeing Husian in the back, especially since the phaser rifle was locked on a kill setting, so Tulb let him go. Ubo told a squad of Husians that he'd never before seen anyone fire a weapon with such accuracy as Tulb. (TOS comic: "Husian Gambit")