The still, silent waters reflect what was, not what is.

Echoing Deeps

You may have Echoing Deeps enter tapped as a copy of any land card in a graveyard, except it's a Cave in addition to its other types.
{T}: Add {C}.

The Lost Caverns of Ixalan

You may have Echoing Deeps enter the battlefield tapped as a copy of any land card in a graveyard, except it's a Cave in addition to its other types.
{T}: Add {C}.

The Lost Caverns of Ixalan Promos

Echoing Deeps copies exactly what was printed on the original land card, with the noted exception.

If you choose to have Echoing Deeps not copy anything, it enters the battlefield untapped.

Any enters-the-battlefield abilities of the copied land card will trigger when Echoing Deeps enters the battlefield. Any "as [this land] enters the battlefield" or "[this land] enters the battlefield with" abilities of the chosen land card will also work.