1) Can i cativate Deck devastation virus on king dragun (does DDV traget)


2) If i play snatch steal on spirit reaper, will he be destroy on my side of the field or before the control is switch? and if its on my side of the field, can i chain book of moon to his effect (of reaper) to keep it on my side?

1. DDVM is like a widespread Fissure. It DOES NOT target since it automatically goes after ANY monster with 1500 or less ATK (Field and hand for initial resolution and whatever is drawn for the next 3 turns).

2. Spirit Reaper doesn't resolve until after the card effect so Reaper will switch sides and then its effect will kick in and destroy itself so it's pretty much automatically happening before you can Book it I think.

I am pretty sure reaper doesnt even switch sides because it says when it is "targeted" by a magic card then it is destroyed by its own effect and since Snatch Steal targets a monster it should destroy reaper. Now if it was Creature Swap then reaper wouldnt be destroyed because Swap doesnt "target" a monster it selects it. Its just how the cards are worded that makes all the difference here.

Actually, the effect of Spirit Reaper kicks in after the card that targets it resolves and after Snatch Steal resolves, Spirit Reaper will be on your side of the field and then self destruct immediately.