Cheapest priced copy (Outlaws of Thunder Junction): $0.35 at Card Kingdom, near mint, their price list as of .
Beastbond Outcaster 
Creature — Human Druid · 3/3 · Uncommon · Outlaws of Thunder Junction · #154
When this creature enters, if you control a creature with power 4 or greater, draw a card.
Plot {1}{G} (You may pay {1}{G} and exile this card from your hand. Cast it as a sorcery on a later turn without paying its mana cost. Plot only as a sorcery.)
Legal inCommanderBrawlStandardPioneerModernLegacyVintage
Not legal inPauper
1 printing · $0.35 to $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Outlaws of Thunder Junction | 154 | Uncommon | $0.35 | $0.49 |
6 rulings from Wizards of the Coast
- 12 April 2024If you’re casting a plotted card from exile without paying its mana cost, you can’t choose to cast it for any other alternative costs. You can, however, pay additional costs, such as kicker costs. If the plotted card has any mandatory additional costs, those must still be paid to cast the spell.
- 12 April 2024When Beastbond Outcaster enters the battlefield, its triggered ability will check to see if you control a creature with power 4 or greater. If you don’t, the ability won’t trigger at all. If the ability does trigger, it will check again as it tries to resolve. If you no longer control a creature with power 4 or greater (usually because the applicable creature is no longer on the battlefield), the ability won’t do anything.
- 12 April 2024Plot abilities are written “Plot [cost],” which means “Any time you have priority during your main phase while the stack is empty, you may pay [cost] and exile this card from your hand. It becomes plotted.”
- 12 April 2024If a plotted card has {X} in its mana cost, you must choose 0 as the value of X when casting it without paying its mana cost.
- 12 April 2024You can’t cast a plotted card on the same turn it became plotted. On any future turn, you may cast that card from exile without paying its mana cost during your main phase while the stack is empty.
- 12 April 2024Exiling a card using its plot ability is a special action. Once you announce you’re taking that action, no other player can respond by trying to remove that card from your hand.