The short answer: Yes, Mr. Hyde’s main pre-workout supplements ARE vegan.
For such a simple question, I couldn't find a clear answer anywhere.
So, I decided to get one myself and publish it here.
I contacted Pro Supps customer support (the company that makes Mr. Hyde) through email to get an answer.
As you can see below, their customer service manager confirmed that Mr. Hyde NitroX, which is their new version, is vegan friendly.
The creatine, which was my biggest concern, is synthetic (not from animal sources).
But what about the original Mr. Hyde product (“intense energy”) that is still sold in a lot of stores?
I followed up again to get more clarification, as shown in the email below:
It turns out that the Mr. Hyde “intense energy” pre-workout supplement is also vegan friendly.
So that’s the long answer: Both of Mr. Hyde’s main pre-workout supplements are in fact vegan.