Glutted Bleeder
Sold by Grumbling Sac. Apply directly to the forehead. Critter type. These creatures have an ability called 'Burst'. When use, they die instantly, thus robbing you of your capture(s).
The Glutted Bleeder is a wild Battle for Azeroth pet that can be captured in the wild, but is notorious for using its self-destruct ability 'Burst' before you can trap it.
Guide awaiting review
Check Abilities Before Engaging
Before attacking a Glutted Bleeder, inspect its ability bar. If 'Burst' appears on the bar, flee the encounter and re-engage — the abilities can rotate between engagements, and eventually 'Burst' will no longer be present, allowing you to capture it safely.
Capture Without Burst Ability
Once you find a Glutted Bleeder that does not have 'Burst' on its ability bar, proceed with the capture normally. If the quality is lower than desired, a 
Grumbling Sac can be used to upgrade it.
