Flightless Bird: Honestly, I’m disappointed. Gary went to the trouble to differentiate Asian and African Elephants, but he’s lumped emus and ostriches together. Anyway, flightless birds first appeared in Supplement III on the wilderness encounter tables, but this is the first time they get stats. Actually, I was wrong about Gary above, because ostriches get 3 hit dice, emus get 2, and rheas get 1. They’re non-aggressive and will run away, but might peck you if cornered.
You know, I’m not so sure about that non-aggressive bit. I’ve been around emus that have become acclimatised to tourists, and they’re pushy bastards. Especially so if you’ve got a handful of chips.
Giant Frog: There are three types of giant frogs detailed here: the regular sort, killer frogs, and poisonous frogs. The regular sort first appeared in Supplement II. Statistically they have changed very little – just their bite damage, which has gone from a flat 1-10 to a different range based on how many hit dice it has. A lot of space is devoted to their average sizes and weights, because they’re used to determine whether the frog can drag its prey with its tongue and swallow it whole. The tongue works much the same as it did in OD&D, drawing its prey in for a bite attack. But now the bite deals maximum damage. And to top it off, they can swallow their prey whole on a roll of 20, and any victim so caught has 3 rounds to get out before dying. Their leap ability has been decreased in distance, but they now get a bonus to surprise. All in all, these guys have gotten a pretty serious upgrade in deadliness.
Killer frogs are smaller, but they have teeth and talons, and love to eat people. And each other apparently, as they’re cannibals. These guys are said to be specially bred mutants, which fits very well with the Temple of the Frog scenario from Supplement II. I guess the killer frogs there flourish even after the temple gets put out of business.
Poisonous frogs are exactly that – smaller frogs that secrete a weak poison from the skin. Not too weak, because the poison is fatal – you just get a bonus to the saving throw.
Violet Fungi: It’s another new monster. They’re purple mushrooms that hide in with shriekers (the mushrooms that make a loud noise when you approach). If you get too close they flail about with tentacles. If these tentacles hit they supposedly rot flesh in a single melee round, but nothing is said about what effect this has. Instant death? Or is it the same as mummy rot? I’d be inclined to support the latter, less deadly version.
I'm not really sure what the purpose of hiding them with shriekers is. Once players have figured out what shriekers are, they tend to stay away, and if they don't go near the big mushrooms the violet fungi can't do much of anything.