I participated in an Ayuhuasca ceremony with a Peruvian shaman a couple years' ago. I set my intention to meet Mother Ayuhausca, or some other benevolent spirit guide, but all I got were weird, gray, psychedelic shapes and images flashing -- robotic dolls, 3D triangles, and other geometric shapes. I wasn't scared, but disappointed. I had hoped for something more...spiritual. Still, others in the room shared far more mystical experiences -- connections with spirits or gaining access to higher truths about themselves and their lives. A few were deeply upset about what they had learned about themselves. Others, deeply moved.
It was my first (and so far only) experience with ayuhuasca. I was told that sometimes it takes a few more tries to connect with Mother A/Spirit, but I'm not sure I can bring myself to trying again. The mixture tastes like tree bark, dirt, and what I imagine that ground up frog would taste like.