Wow, yeah that trample is a lot more devastating than I thought. In MTG the trample effect only passes on any any residual attack points from the first creature killed.
I.e the trample card has an attack of 6 and the defending card has a defense of 4, the remaining 2 would be used to trample the next creature. In this case it is more repeated attacks, so long as one dies, it's attacking again at full strength.... That's some power!