Tarrant County convicts Kaeden Farish, 19, to 19 years for fentanyl-related murder under new law. Farish sold fentanyl-laced pills to a 17-year-old who died. Fentanyl, 50x more potent than heroin, is the deadliest drug threat in the U.S., causing 66% of 2021's 107,622 overdose deaths. Rainbow fentanyl, brightly colored, aims to target young adults. Narcan, an opioid antagonist, temporarily reverses overdoses and is now over-the-counter.