ok it says select a union monster in your grave and equip it to the correct other half on the field, seeing as this is a trap card, if there is only one guy on your side of the field and your opponent attacks, assuming youve got the correct half in the grave, would a replay occur???

ok, example,

player A has a puny aitsu in attack mode, one face-down in the zone
player B summons kycoo and attacks
player A activates Roll Out! and targets koitsu,

does a replay occur? i dont think so since player A never changed the number of monsters on his/her side of the field... but if not then can i assume that kycoo now smacks head on into the 3100 aitsu??? thanks...

I would say no, no replay would occur. The reason is because it is being equiped to a monster, and never touching the monster zone. This situation would be more like activating a spell/trap that boosts your monster's Atl/Def. So Kycoo would have to run right into the pointed end of those paper airplanes.

ok thanks, this card could actually make for a cool paper airplane deck... lol