Activating End Effector Rotation
If you want to lock certain bones still but allow them to rotate, you can activate the End Effector Rotation feature. It is suitable for creating tiptoe motion or nailing down both ends for a certain bone chain.

With the End Effector Rotation feature, you can have the character perform a tiptoe pose by only dragging the ankles.
- Create a new standard character.
- Open the 2D Motion Key Editor.
- Move the hip down and have the body leaning forward.
- Set the hands positions.
- Activate the Constraints and End Effector Rotation boxes.
The end effectors' color will turn magenta. - Select one of the ankle bones with the end effector.
- Drag the ankle bone. The bone with the final end effector of the chain (leg) will be locked but still rotatable.
- Repeat the same step for the other foot.
Optionally adjust the angles of the toes. - The character strikes a tiptoe pose afterward.

If a bone chain contains more than two end effectors, than you can take advantages of the characteristics of the bone chain and end effectors to fasten both ends (root and end bones) of the chain while the other bones are free to animate.
Keep in mind that the when the End Effector Rotation is activated, the bones attached with end effectors will always be nailed down but rotatable when the other bones with end effectors or the root bone of the chain are animated.
- Create a free bone character. In the Composer mode, the bones are deliberately set to pattern of Z to keep ample space for movements.
- Create end effectors at the middle and the end bones.
You can optionally create the Rig GUI after this step. - Switch to the Stage mode.
- Make sure the character is selected and open the 2D Motion Key Editor.
- Activate the Constraints and End Effector Rotation boxes.
- Select and animate the mid-bone with end effector. As you can see the root and the end bones of the chain stay still while the other bones are free to move.
- Set keys in different time frames to create a character that wriggles while the both ends are held.

If you select any other bones in yellow (no end
effector attached), then the bone chain will perform as usual. The end effectors do not
have any effect on the chain.
