Cheapest priced copy (Commander 2020): $0.49 at Card Kingdom, near mint, their price list as of .
Ethereal Forager 
Creature — Elemental Whale · 3/3 · Rare · Commander 2020 · #34
Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
Flying
Whenever this creature attacks, you may return an instant or sorcery card exiled with this creature to its owner's hand.
Legal inCommanderLegacyVintage
Not legal inBrawlStandardPioneerModernPauper
1 printing · $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Commander 2020 | 34 | Rare | $0.49 | — |
5 rulings from Wizards of the Coast
- 17 April 2020If Ethereal Forager leaves the battlefield while its triggered ability is on the stack, that ability can still find the cards exiled with Ethereal Forager’s delve ability.
- 17 April 2020After Ethereal Forager’s triggered ability resolves, players will have priority to cast spells (such as the card you returned to your hand, if it’s legal to do so) before blockers are declared.
- 19 March 2021Because delve isn’t an alternative cost, it can be used in conjunction with alternative costs, such as flashback. It can also be used to pay for additional costs that include generic mana.
- 19 March 2021You can exile cards to pay only for generic mana, and you can’t exile more cards than the generic mana requirement of a spell with delve. For example, you can’t exile more than seven cards from your graveyard to cast Treasure Cruise unless an effect has increased its cost.
- 19 March 2021Delve doesn’t change a spell’s mana cost or mana value. For example, Treasure Cruise’s mana value is 8 even if you exiled three cards to cast it.