I'd avoid these tabs - for these reasons:
-the 25x series tends to be risky to begin with.
-there is a big difference between 25c and 25b, if you don't know which one you're taking it's a big increase in risk.
-the mixture of two 25x further adds to the unpredictability.
-you don't mention dose sizes of each, something you'd definitely want to know and confirm with 100% accuracy before you ingest any of these 25x chemicals.
The only way you should ever consider taking these tabs is if you can find out exactly what is on them and in what dosage. Once you know that, read up on the respective Bluelight threads for each chemical, check out the warnings, and if you still want to go ahead with it, keep notes because I don't think too many people have combo'd these before (I could be wrong).