Cheapest priced copy (Commander Legends): $0.35 at Card Kingdom, near mint, their price list as of .
Brass Herald 
Artifact Creature — Golem · 2/2 · Rare · Eighth Edition · #293
As this creature enters, choose a creature type.
When this creature enters, reveal the top four cards of your library. Put all creature cards of the chosen type revealed this way into your hand and the rest on the bottom of your library in any order.
Creatures of the chosen type get +1/+1.
Legal inCommanderModernLegacyVintage
Not legal inBrawlStandardPioneerPauper
4 printings · $0.35 to $2.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Eighth Edition | 293 | Rare | $0.49 | — |
| Eighth Edition | 293★ | Rare | — | $1.49 |
| Apocalypse | 133 | Uncommon | $0.39 | $2.49 |
| Commander Legends | 301 | Uncommon | $0.35 | $0.49 |
3 rulings from Wizards of the Coast
- 10 November 2020You must choose an existing creature type, such as Human or Warrior. You could even choose Coward, if you dared. Card types such as artifact and supertypes such as legendary can't be chosen.
- 10 November 2020Because damage remains marked on a creature until the damage is removed as the turn ends, nonlethal damage dealt to creatures of the chosen type may become lethal if Brass Herald leaves the battlefield during that turn.
- 10 November 2020The choice of creature type is made as Brass Herald enters the battlefield. Players can't take any actions between the time the choice is made and the time the appropriate creatures begin to get +1/+1.