It does give the opponent four life, but this downside is hardly impactful, especially considering you'll likely have a field full of creatures to take it away just as quickly as they got it
As it was originally released in Shrouded Fable but became a staple in many other decks to be able to get cards back out of the discard pile, it is great that it is now reprinted in a set that is likely going to have a lot of extra copies of reprints and commons
In this case, you shouldnt mix real cards and proxy cards without using sleeves, because proxies can be easily identified in other zones such as your library or your hand
Today, its a black hole of disputed transactions, missing packages, obnoxious fees, and grey-market surgical equipment
Bouncing a permanent or spell every time you cast another spell is a recipe to get ahead quickly, and the 7/8 attacker helps convert the lead into a win