Blends the Base Pose with a number of other poses defined based on an alpha value per blend pose. Blend poses can be added and removed via the right click context menu or by using the “add pin” button on the node.

Warning: As of Unreal 5.3, removing all blend pins and leaving only the base pose on the node will crash the editor as soon as it gets evaluated for the first frame!

Every blend pose has an associated alpha value and is able to completely or partially override blend poses that came before if the setups would modify the same bones(blend pose 0 will override the base pose and blend pose 1 will override blend pose 0, etc.).

The setup of which bones get blended can happen in 2 ways:

Blend Mode: Branch Filter

Using a branch filter, every blend pose will have an array of filters associated in the nodes’ details. This is the default setting of the node. Each filter is able to dicate from which bone the pose will take effect and how deep the effect should go in the hierarchy.

For more reference on the nuances of branch filters, take a look at this forum discussion

Blend Mode: Blend Mask

Setting the blend mode to “Blend Mask” will remove the branch filters and instead associate a blend mask for each blend pose on the node. Blend masks need to be configured on the skeleton asset the animation blueprint is based on, before they are available on the node.

A note on the use of Blend Masks and Template Animation Blueprints

The blend masks available in the node are queried from the associated skeleton of the Animation Blueprint. Due to Template Animation Blueprints not having a skeleton assigned, it is not possible to select a blend mask, eventhough the blend mode can still be set to ‘Blend Mask’ Since the AnimGraphs of child classes are ReadOnly, this cannot be changed in child classes that have a skeleton assigned, effectively making this mode useless in Template Animation Blueprints.

Other than the blend mode, the node has options to blend rotation and scale in Mesh Space, as well as on how AnimCurves should be blended and how the node may affect rootmotion.