Same here. My Frinshaw pet has 159 def (with armor) and Full on Defensive mode, but it's got KOd at
shroom balls!
By the way, I think that's because of this: I just browsed the forums, and I have found one topic where coke_na_rc had a glitch that his pet had fallen off of the map at magmagons (the pet had around 200 def), and coke just killed mags and the pet didn't die (
http://helmet-heroes.com/forum/viewtopic.php?f=4&t=42528). So
robby made an update where the pets die when falling out of the map, like players and monsters, and i think the game thinks the pet is in the void and it dies for no reason.
IT'S FIXED NOW! THANKS ROBBY!!!