Let’s come up with a monster.

It would be great to focus on making creature abilities more original! For example, a level 7 monster – Wrath of Nature! A fusion of all the plants, fungi, and trees in the world, with the heart of animals of all kinds! You could place an archer or pikeman on this "fusion" as if it were a tank. Abilities: "Shelter," "Vulnerable to Fire," "Large Creature" (4 squares), and "Vines" – the ability to be useful during a siege. It extends vines through the castle walls, and a warrior can walk along them.