Surftech AIPA Dark Horse/ Dual-Core SurfboardAIPA Dark Horse Dual Core During the testing phase of the Dark Twinn, Duke wanted to feel the point of difference if it was reconfigured for a quad arrangement. As a fraternal sibling of the Dark Twinn, The Dark Horse was developed as the quad specific adaptation of the design with every element of the 2 designs being identical , except for shifting the wing forward to correlate with the quad forward fins. The result was a more controlled predictable