Cheapest priced copy (Murders at Karlov Manor): $0.35 at Card Kingdom, near mint, their price list as of .
Tunnel Tipster 
Creature — Mole Scout · 1/1 · Common · Murders at Karlov Manor · #180
At the beginning of your end step, if a face-down creature entered the battlefield under your control this turn, put a +1/+1 counter on this creature.
{T}: Add {G}.
Legal inCommanderBrawlStandardPioneerModernLegacyVintagePauper
1 printing · $0.35 to $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Murders at Karlov Manor | 180 | Common | $0.35 | $0.49 |
One ruling from Wizards of the Coast
- 2 February 2024Tunnel Tipster's first ability will trigger as long as a face-down creature entered the battlefield under your control this turn, even if that creature has turned face up or left the battlefield since. A creature that enters the battlefield face up and turns face down later in the turn won't cause Tunnel Tipster's first ability to trigger.