The Guavian Death Gang and their negotiator Bala-Tik encountered Han Solo and Chewbacca on the freighter Eravana. They were accompanied by Kanjiklub when they threatened Han Solo and expressed their impatience with him and his endless excuses, after Solo delayed on repaying them the 50,000 credits he foolishly borrowed.
When Bala-Tik recognized BB-8, he told Solo that the First Order was looking for the droid and for the fugitives Finn and Rey. Upon hearing this, Rey thought of activating the blast doors on either side of Han and Chewbacca to trap both the gangs. Rey activated the wrong doors, releasing the three rathtars Han Solo was keeping on his freighter.
The rathtars devoured most of the Guavian Death Gang and Kanjiklub, leaving only Bala-Tik and possibly a few other soldiers. During the battle, Han Solo and Chewbacca escaped on the Millennium Falcon with BB-8, Rey, and Finn. Bala-Tik then contacted the First Order and told them that BB-8 was on the Millennium Falcon.