If you somehow control Battle of Hoover Dam and no choice was made for it (perhaps because another permanent on the battlefield became a copy of it), it has neither of the two triggered abilities
Pain Amplifier is unfortunately blocked by Unown G's Guard PokePower, but the attack is still useful as a free attack to spread damage
Oswald Fiddlebender Oswald Fiddlebender is a nifty little card
Its unfortunate that the only creature that can do more populating once copied is Wayfaring Temple, unless of course youre equipping Trostani, Selesnyas Voice with Helm of the Host
Wincons outside of typical black combo pieces, especially the Revel in Riches and Marionette Master pieces to take advantage of those Treasures, are a bit lacking in Mari's supported creature types
This means we have no idea how many people played their deck in the event as a whole, which means we don't know what the conversion rate is from 0-0 to 4-0/3-1