Core Set 2019 has Scapeshift, Omniscience, and Crucible of Worlds: far better pulls than I would have expected going into preview season
While this wont grab land cards from your deck, if you combine it with some incidental card draw thanks to other colors, you can quickly end up with an unmatched number of Lands on board
See rule 701.47, Amass. 701.47a: To amass [subtype] N means If you dont control an Army creature, create a 0/0 black [subtype] Army creature token
I cant in good conscience show you that
Dark Machamp may be under the control of Team Rocket, but there's no telling what unique versions you may find
Megara, Secret Keeper, on the other hand, is an early game card with a cost of three that gains the ability to force the opponent to discard a card when she is challenged once boosted with a card underneath it