Base class for [AnimationNode]s with more than two input ports that must be synchronized.
An animation node used to combine, mix, or blend two or more animations together while keeping them synchronized within an [AnimationTree].
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- If [code]false[/code], the blended animations' frame are stopped when the blend value is [code]0[/code]. If [code]true[/code], forcing the blended animations to advance frame.