I don't think the ideas are very good... frogs – will they "jump" onto the enemy, and how will they even attack? It would be better to make frogs as a background element of the city (decoration), and the troglodytes as Neanderthals who can't see anything because they lost their eyesight over time due to the darkness))) Where they live – in caves or a bolt – doesn't matter; they can be found in both))) Mud – it's awful... in my opinion... if you're creating a swamp, it doesn't mean that everything should be related to mud, and if that's the case, there's not that much mud in a swamp!!! There's much more reed)))) or moss))))
Guards – "a dog that's all covered in black swamp mud")))) What is this? You've just discovered America and come up with new hellhounds))

P.S.: Forget the idea that an upgraded unit must necessarily poison, but feel free to share your ideas...