This oddly reminds me of my puffer giraffees' slug-rage.
We had a fairly moist period near the end of summer, which resulted in a lot of slugs in my garden. Since my puffer giraffees love eating all sorts of insects, it seemed logical that they would love a slug (so my husband suggested). So he takes a big juicy live slug from the garden, gingerly washes it off, then tosses it into the tank. Sure enough Hoju (the aggressive green spotted puffer) goes for a taste, realizes he loves it with enthusiasm, and gobbles it all up quicker than anything. At that point Valentine (the docile Ceylon puffer) sees Hoju eating something tasty and swims over all "hey, what's going on? Did you find something tasty?" To which Hoju just flips out into a puffergiraffe rage and attacks Valentine. Hoju is aggressive, but he and Valentine have been buddies for almost their entire lives, and Hoju rarely ever gets pissed off at Valentine - maybe twice before in the 5+ years I've had them. The husband and I both thought this was odd, but clearly the Hoju loved the slug - after all it's mostly meat.
Clearly, Hoju likes slugs, so the next time we're in the garden, I find several more slugs, and the Husband says we should give them each a slug, so that Valentine can have a taste too. This time when we toss the slugs in it's Valentine that notices first, but we've added two slugs, and Valentine gobbles one up just as Hoju notices, and goes for the other one. Before Hoju can get to the slug, it's Valentine that flies into a slug-induced-rage and attacks Hoju - which has never, ever happened before. Valentine's so gentle that the dude is afraid of snails.
We continued to test this slug situation out, and it seems that even if they both get a slug at the same time, as we tried later, it induces a feeding frenzy followed by rage. They eat the slugs in a more excited manner than any other thing I've fed them, then they are furious when there's no more - they'll even attack inanimate objects like the drift wood, or plastic cave because they are mother-fuckin-angry that all the slugs are gone. This doesn't happen with any other foods, including several live foods such as snails, worms, ghost shrimp, guppies, or any other variety of insects. Odd.
Hrm. Rereading this post, it just occurs to me that I live a strange life. But oh well. So what. At least when I have a fly or spider or whatever in the house, it's an adventure wondering which of our pets will eat it. The cats love moths as well, and find them delicious.