{T}: Add {C}.
{2}, {T}, Sacrifice Demolition Field: Destroy target nonbasic land an opponent controls. That land's controller may search their library for a basic land card, put it onto the battlefield, then shuffle. You may search your library for a basic land card, put it onto the battlefield, then shuffle.
If the targeted land is an illegal target by the time Demolition Field's ability resolves, it won't resolve and none of its effects will happen. Neither player will get to search for a basic land card.
The target land's controller gets to search for a basic land card even if that land wasn't destroyed by Demolition Field's ability. This may happen because the land has indestructible.