Ivy and Bo, Deft Documenters

Whenever Ivy and Bo attack, choose up to
one permanent without a photo counter on
it. Then, you may pay {x}, where X is that permanent's converted mana cost. If you
do, put a photo counter on that permanent
and create a token that's a copy of it. If it's a creature, the token is tapped and attacking. Exile that token at the beginning of the
next end step.