This is Dragon Magazine 25, from May, 1979. The issue is largely dedicated to Gamma World and boy, that cover is a classic. Would you believe it is by Phil Foglio? I had no idea. The perspective is so delightfully weird and the mutant (?) so perfectly bizarre.  

This is one of the few issues I own with the cardboard mailing cover intact, which is pretty cool. The dragon there, of course, is the same one that graced the cover of the first issue.