duskmourn mtg most expensive cards target attacking creature gets +1/+0 and gains first strike until end of turn. Overlord of the Boilerbilges –

Zell Dincht gave us an extra land drop with a drawback

Ominous Seas Ominous Seas is too low impact to make a splash in any Constructed format

It has more synergy in a creature-based reanimation build that wants creatures, but they are close enough that both are here

White players who like to complicate combat have been making use of Angelic Skirmisher for years, so a version of that targeting just one creature but at half the cost might generate interest to some

Fairly easy to do in Mono Black and the token creation isnt limited to once a turn either

With the other cards, we're talking about alternate win conditions or support tools