Martok said:
Normal monsters are unaffected by Skill Drain.
Not to put too fine a point on it, but it might be better to say that Skill Drain ONLY effects Effect Monsters, rather than the other way around. (We have seen where NOT something does not mean it's oposite being true-e.g. the E-Hero Elemental issue that got his signiture).
It is an effect, a continuous effect at that, which treats him as a Normal Monster. Different is the effect of Wildheart that allows him to ignore effects. Looking at it from the perspective of Skill Drain, it looks around the field looking for Effect Monsters. It sees a Gemini Monster, who looks as though it should be an effect Monster, because it senses that there is an effect going on. however, the harder it looks at the card, it just plain looks like a Normal Monster. So, it passes. Well, at least that is how it would work on TV
But, this is YuGiOh! TCG where anything can happen. Rather that looking at it from Skill Drains perspective, we look at it from a Field perspective, wherein a condition is now placed upon the field to wit, any effect is negated UNLESS there is an effect which prevents, or ignores Skill Drain (such is the case with Wildheart). Geminis do not negate or ignore anything in and of themselves. So, they, even though they may be currently treated as Normal Monsters not having an effect, will still be negated. Thus making them negated Effect Monsters. That seems logical.
Yeah, I could see it going either way. Still, I think it will go the first way in the end. Because YGO logic rarely follows reality.
As for when Skill Drain leaves the Field, what would happen? Well, if Fusilier Dragon has any bearing: (from RONIN) "
"¢ If you Summoned this card without Tribute, and then "Skill Drain" is later activated, the ATK and DEF are no longer halved. If "Skill Drain" is later destroyed, the ATK and DEF still remain 2800/2000."
I guess we just have to wait and see.