Cheapest priced copy (Wilds of Eldraine Promos): $49.99 at Card Kingdom, near mint, their price list as of .
Agatha's Soul Cauldron 
Legendary Artifact · Mythic · Wilds of Eldraine Promos · #242p
You may spend mana as though it were mana of any color to activate abilities of creatures you control.
Creatures you control with +1/+1 counters on them have all activated abilities of all creature cards exiled with Agatha's Soul Cauldron.
{T}: Exile target card from a graveyard. When a creature card is exiled this way, put a +1/+1 counter on target creature you control.
Legal inCommanderBrawlStandardPioneerModernLegacyVintage
Not legal inPauper
4 printings · $49.99 to $199.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Wilds of Eldraine Promos | 242p | Mythic | $49.99 | $69.99 |
| Wilds of Eldraine Promos | 242s | Mythic | — | $89.99 |
| Wilds of Eldraine | 242 | Mythic | $54.99 | $74.99 |
| Wilds of Eldraine | 366 | Mythic | $79.99 | $199.99 |
3 rulings from Wizards of the Coast
- 1 September 2023The granted abilities effectively use "this permanent" rather than "[that card's name]," so you treat the abilities as though they were printed on the creature that gained the ability. For example, say you exiled the card Argothian Sprite with Agatha's Soul Cauldron. Argothian Sprite has the ability "{7}: Put two +1/+1 counters on Argothian Sprite." If you controlled a Callous Sell-Sword with a +1/+1 counter on it, you'd treat it as though it had the ability "{7}: Put two +1/+1 counters on Callous Sell-Sword."
- 1 September 2023Agatha's Soul Cauldron grants only activated abilities. It doesn't grant keyword abilities (unless those keyword abilities are activated), triggered abilities, or static abilities.
- 1 September 2023Activated abilities contain a colon. They're generally written "[Cost]: [Effect]." Some keyword abilities are activated abilities and will have colons in their reminder text.