A bipolar concept slider for muscle mass and definition, no trigger word, the LoRA weight itself is the control. Weight 0 = no effect (base model). Negative weights move toward a slender body with no visible muscle; positive weights move toward a heavily muscled, powerfully built physique.

V2 Changelog:

• No ethnicity drift at any tested weight, either gender

• Generalizes correctly across ages it was never trained on

• More robust past the trained range

• sharper muscles Definition compared to V1

V1:

Recommended range: -3 to +3. ±4 is usable but pushes further into an extreme the training data covers more thinly.

What makes this one different: the same single axis was trained and verified to work across three structurally different subject types, human men and women, fully mechanical androids (build reads as light chassis ↔ heavy armour plating), and anthropomorphic/furry characters. Sample images show all three.

Known limitation: on some human female subjects, the extreme positive end (+3/+4) can show a subtle shift in apparent facial features alongside the muscle growth. A fully "locked" prompt (explicit hair, skin tone, pose, and clothing described in detail) noticeably reduces this.

Usage tip: for best results describe hairstyle, skin tone, pose and clothing explicitly and hold them fixed across your renders, a sparse prompt gives the model room to change things you didn't intend along with the trait.