Cheapest priced copy (Bloomburrow Commander): $0.49 at Card Kingdom, near mint, their price list as of .
Shield Broker 
Creature — Octopus Advisor · 3/4 · Rare · Bloomburrow Commander · #174
When this creature enters, put a shield counter on target noncommander creature you don't control. You gain control of that creature for as long as it has a shield counter on it. (If it would be dealt damage or destroyed, remove a shield counter from it instead.)
Legal inCommanderLegacyVintage
Not legal inBrawlStandardPioneerModernPauper
4 printings · $0.49 to $2.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Bloomburrow Commander | 174 | Rare | $0.49 | — |
| New Capenna Commander | 29 | Rare | $0.49 | — |
| New Capenna Commander | 130 | Rare | $0.49 | — |
| New Capenna Commander Promos | 29p | Rare | — | $2.99 |
7 rulings from Wizards of the Coast
- 29 April 2022If a permanent that would be dealt damage has more than one shield counter on it, that damage is prevented and only one shield counter is removed.
- 29 April 2022If a permanent with a shield counter is dealt unpreventable damage, that damage will be dealt and a shield counter will still be removed.
- 29 April 2022Shield counters don't prevent players from sacrificing creatures.
- 29 April 2022Removing a shield counter in this way isn't the same as regenerating a creature.
- 29 April 2022If the creature loses its shield counter during combat, it will be removed from combat when it changes controllers. If it hasn't already assigned combat damage by that time, it won't get to deal combat damage.
- 29 April 2022"Shield" is not an ability that creatures have and shield counters are not keyword counters. If a creature with a shield counter loses its abilities, the shield counter will still protect it as normal.
- 29 April 2022A creature with a shield counter on it may still be destroyed by state-based actions if it has damage marked on it equal to its toughness or has been dealt unpreventable damage by a source with deathtouch.