In R/B/Y any attack that did set amount of damage ignored the type chart completely. Was playing yellow a few weeks ago and someone seismic tossed my gengar xD.
Also in first gen dragonair has no real weakness to dragons since the only dragon move in the game always deals 40 dmg and ghosts were weak to other ghost type attacks but the only ghost attack that dealt variable damage was lick (which lickitung couldnt learn wtf!)
Also in first gen dragonair has no real weakness to dragons since the only dragon move in the game always deals 40 dmg and ghosts were weak to other ghost type attacks but the only ghost attack that dealt variable damage was lick (which lickitung couldnt learn wtf!)