Lots of brown snakes where we are, had a 7 footer in the garage last summer.
They are seriously deadly. We had a staffy once that attacked one and got bitten on the face, he went into convulsions within a minute and it was only that the vet was just 1/2km away from us that he got antivenom that saved him. Any further he'd have been gone. They deserve a more deadly name than just brown snake, but we Aussies are lazy and I guess when it was being named it was "what'll we call it? Mmmm...its brown, how about a brown snake? Yeah that'll do"
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The redbacks are venomous but you'd be unlucky to die from a bite. A person with an underlying condition may. We do have an unclassified much worse one that resembles the funnel web and is believed to be as deadly as the New South Wales ones. Thankfully they are scarce. I hate our bulldog ants. They can reach 5cm long and have a venom stinger in the abdomen. The pain from one is almost unbearable. They latch on with their mandibles and keep on keeping on injecting. One got my leg once and I couldn't walk properly for a week, my calf swelled twice the size, was hot to touch and almost the entire calf muscle area was full on black and blue bruised. They are evil on steroids and will go for you on purpose. I had them drop on to me from a tree once. They are everywhere where we live. I hate them with a passion. If they are within 10 to 15 meters and your digging out a target they will get agro and come for you. People have died from them.
Several types, the huge black ones are the worst.
The roos are ok, just a big rogue loner are the ones to avoid. 99.9% are no problem. They will drown a dog though. Yrs ago one of my dogs chased one and if there is water and they feel there is no option they go into the water to midway depth. When the dog goes in to get it the roo will grab its head and drown them. My dog did that and had his head held under a couple of times but finally after calling got free and came back.
Where we are its the browns and bulldog ants I avoid.
Magpies are ok in the bush, ones here are really peaceful. In towns though they seem to get aggressive during nesting season, attacking people and each other. I have never seen bush magpies do either any time of year nesting or not. No idea why the difference between ones in towns and cities compared to little places like where we are.