your dog can be stolen by greed if they reach it before they reach you, but the dog doesn't die and you can get the dog back after destroying the cave and defeating the greed on the island that you lost the dog on. however, the dog does whine the entire time it's being taken away, and the sound can be distressing.
if you really need to avoid this, you can neglect to ever unlock the dog from the tree it's hiding in and you can't risk losing what you don't have. the dog is useful for warning when greed are on the way and what direction they're coming from, but once you get the hang of the game i would say it's not needed to succeed
the bowmen you recruit in every version of the game hunt randomly generated sprites of various birds, small mammals, and deer. there is no blood or a death animation really, they just immediately turn into coins.
if your dog is abducted by greed, it whines the whole time. but you are able to save the dog and win it back by defeating the cave on the island that you lost it on
yes, but only in the classic European style of the game. in Shogun, Norse Lands, Dead Lands, and Call of Olympus, there are small fowl/raccoons/squirrels in other versions of the campaign
even if you lose, your game technically doesn't end (except in challenge modes). it just gives you a descendent of your previous monarch and sends you back to the first island with all mounts and statues needing to be unlocked again (only with coins this time, not gems first. so it's easier) but all of the workers you had hired are still there and whatever level you had built any of the castles to does not revert
so it makes you start over in a sense, but it's clearly a continuation of the same campaign
there's a mount you can unlock in the Call of Olympus campaign that is the giant spider Arachne, and in that version of the game the mounts are placed on random islands in each campaign played, so it could appear on any of them
only the greed if you use a mount that can leave a trail of fire behind them as a charge-up ability, or if you're playing in Norse Lands or Call of Olympus and turn archer towers into fire towers
there are certain mounts that are large bugs/spiders, but they can be avoided being seen pretty easily by running past them quickly and aren't necessary to unlock to succeed at the game
when your mount is running out of stamina, they pant as a visual and auditory countdown cue, but it's from being out of breath from running and doesn't sound labored at all
in the Call of Olympus version of the campaign, there is a very giant snake destroying the last island that you have to fight off for a significant portion before the final battle
in the Plague Island challenge mode, your citizens can be greedified in some kind of zombie virus that spreads through contact, and it could look like being possessed
if you really need to avoid this, you can neglect to ever unlock the dog from the tree it's hiding in and you can't risk losing what you don't have. the dog is useful for warning when greed are on the way and what direction they're coming from, but once you get the hang of the game i would say it's not needed to succeed