They USED to be, but when I started actually writing stuff out I decided to go in a different direction so I kind of phased out the markings for the most part. Some of them still have them or an equivalent, like Mini and Lotte (although I might mess with the designs/placement) but now they're less an indicator of a contract with Xandria in particular. I honestly forgot about Lyssa's entirely because it's been so long since I've drawn her where her lower back wasn't completely obscured by her ass but I might bring that one back cuz it's hot and she's the only character who, in setting, actually made an explicit contract (Chris and Vivi just had it kind of inflicted upon them lol)

Theoretically it's limited by Xandria's influence and power (which Pietra acts as a conduit of) but that is in and of itself so unfathomably vast that there's not REALLY a limit. If anything it's more a matter of how much the world can handle, because it's nature is very reality warping and things kind of start falling apart past a certain point, like on a "how could a living being be this large and still function" logical failure level, which would be around like, stepping-on-skyscrapers size.

It's also limited by WHERE she is. There's effectively 3 "layers" of reality to the setting—the normal world outside of Alexandria, Alexandria the city/location, which is kind of like an alternate dimension bolted onto and over chunks of the normal world, and then the underlying layer that exists beneath that. Outside of Alexandria she's much more limited, probably "only" capable of growing to around 50 feet. Inside Alexandria she's capable of the insane sizes previously mentioned, and then in the underlying layer (which I THINK I allude to in those early stories—it's where she comes from when she just kind of busts through reality like it was made of glass and walks out of a weird portal) there's basically no limits, she can go full on apotheosis bigger than entire planets level.