Scale and size restrictions

MFZ uses what is called the 7p scale. Essentially, an average human is 7 plates of LEGO® tall. That means that anything else modeled should reflect this, so when two forces meet, they look roughly at the same dimensions. 7 plates is two bricks and a plate on top.

As loose rule of thumb, frames should generally fit inside a box that is 10 studs wide, 10 studs deep and 12 bricks tall. There is some wiggle room for quadrupeds, but it should generally be observed as the maximum. Size creep can quickly become an issue. Since there is a definitive size for humans, this also requires some space where the human can fit inside a frame — generally, the torso. Otherwise, MFZ has no restrictions on what a frame should look like, what colors or parts to be used, and if you don't want to use LEGO®, a Gundam model with removable systems is fine, too.