This is the sequel to Figuring Out Giganto and covers the potential adverse effects of Gigantis, namely excessive size.
You see, Gigantis defies the square-cube law, allowing for the strength of a Giganto's body's support systems (muscle, bone, thermoregulatory and circulatory/respiratory systems) to increase proportionately with size. It also keeps speed and metabolism the same as size increases. (Look at the question for greater detail.)
However, this allows it to grow to ridiculous sizes, becoming stronger and tougher as it grows, until it's about the size of a mountain. I don't want that. Contrary to appearances, I want the humans in my setting to live, which is why I made Enchantments a thing. Thus, something has to keep Gigantos in a reasonable size range.
My current ideas are:
1. Parasitism: Eating a creature gives you its Enchantment, so logic follows that if you eat part of a creature, you gain part of its Enchantment. This means otherwise innocuous parasites, leeching off a Giganto's body, will also be leeching off its magic and therefore inhibiting its size.
If what I've heard about smaller theropods eating off sauropods, essentially acting as large parasites, is true then Chompers and Plop could fulfill this function, gaining their growth abilities from Gigantos.
2. Predation: The larger a Giganto, the more Chaos Energy it has. Chaos Energy is the force behind leveling, the stuff that fuels Enchantments, so magical creatures (AKA monsters and adventurers) will be drawn to Gigantos, especially powerful monsters that take more CE to level up. Thus, it's not that they can't become bigger, it's that they don't because the big guys always get killed and/or eaten before too long.
However, this could easily backfire; Gigantos are conscious of their own Enchantment, they know what it does, so it makes sense that young Gigantos will try to hunt down and eat older, bigger Gigantos so they can get just as big and strong, and vice versa. This predation would thus be counterproductive, as it would allow Gigantos to become even bigger than a mountain.
3. Parenting: Hatchlings and young Gigantis are relatively small and weak compared to their adult selves, so it seems that predators would target them. Thus, Gigantos need to reach a large size, namely 5x larger than a meter long hatchling minimum ASAP before they can be realistically safe.
There are only two solutions for this: one, the Gigantos vigilantly defend their offspring, even with their very lives, or two, one or both of the parents gets eaten by said offspring. One comes with the issue of granting Gigantis to whatever killed the parents, making parental defense effectively useless for my purposes, and the second seems counter to natural selection. I know some insects pursue similar strategies (one word: matriphagy), but why would mutant theropods do the same?
Thus, because I am at my wit's end here, I am asking: What Strategy Would Best Keep Giganto Size In Check?
Specifically, which strategy would be most efficient and create the least amount of dangerous (as in dangerous to medieval Europeans) monstrosities?