Cheapest priced copy (Theros Beyond Death): $1.79 at Card Kingdom, near mint, their price list as of .
Dream Trawler 
Creature — Sphinx · 3/5 · Rare · Theros Beyond Death · #214
Flying, lifelink
Whenever you draw a card, this creature gets +1/+0 until end of turn.
Whenever this creature attacks, draw a card.
Discard a card: This creature gains hexproof until end of turn. Tap it.
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
4 printings · $1.79 to $7.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Theros Beyond Death Promos | 214p | Rare | $2.29 | $2.99Out of stock |
| Theros Beyond Death Promos | 214s | Rare | — | $3.49 |
| Theros Beyond Death | 214 | Rare | $1.79 | $2.49Out of stock |
| Theros Beyond Death | 336 | Rare | $5.49 | $7.99 |
2 rulings from Wizards of the Coast
- 24 January 2020You can activate Dream Trawler's last ability even if it's already tapped. It still gains hexproof until end of turn.
- 24 January 2020Dream Trawler's second triggered ability resolves before blockers are declared. This normally causes its first triggered ability to trigger, which also resolves before blockers are declared.