This morning I had a rather close duel where I figured something out really cool with Angel Trumpet that I now I have to scour the card list to see if it can be applied elsewhere. My opponent had Estoma on his field, and even though I had a pretty strong field presence (and very few cards to play) I decided to angel trumpet him just for the heck of it. My opponent decided to use his action skill doubling his attack and range. Turns out the card took the current attack power and made it PERMANENT! So now he had a 2nd row tank unable to do anything for the rest of the duel. Was rather pleasantly surprised.
Just thought I'd share this nugget.