Silver

Here are some of my candidates:

Sound the Alarm

Information is very powerful in this game, and Sound the Alarm gives you great information on what's coming from the other side of the table while still having good stats. A lot of generics with cool effects are sadly 2 blocks, but not this guy! Sometimes you also get to search for a D react, which is admittedly not always amazing in this format since we miss out on the best ones, but most heroes have some decent options they might want to run. I use it in my Pleiades deck where What Happens Next? can make it a 0 cost play, which is oh so satisfying. And I also love setting up Emboldened by the Crowd.

Loot the Hold

What can I say? This is such a power card for Gravy Bones, enabling the hero ability and providing a very scary on hit effect. Always a good time when you draw this.

Herald of Victoria

Modal cards are really cool, and this herald feels like it can fix any hand. It can pitch, it can attack and it has a special trick on either offence or defence. Would be amazing if it also went to soul, but that might be asking too much.

V of the Vanguard

This is one of the new playable non-equipment specializations in Silver Age, and is such a big card for Boltyn. V of the Canguard power turns are great! I wish more heroes had access to cool "pop off" cards like this. Specializations just feel kinda cool!