This title kinda made me lol and I see no explicit reason why it would be dangerous, but always best to start low with any combination. I know some other things similar to tadalafil can cause an increased sensitivity to light, and given the pupil dilation caused by LSD & 2c-e you might want to make sure to avoid bright lights, but if that would be anything more than uncomfortable/annoying i'd be kind of surprised. Tadalafil does inhibit PDE11 which is present in the brain, but i have no idea what it does. Do be aware of normal contraindications with Cialis (tadalafil) & make sure you're compliant with those before adding LSD/2c-e to the mix. Both 2c-e/LSD & cialis do modulate blood pressure via constriction & dilation of blood vessels, respectively, so do be careful. Though if anything these should mitigate each other's effects in that regard. To what degree i'm entirely unsure.
If anyone knows any reason why this would be ill advised do tell