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Hi. I've got an issue in new game in shandalar. At my highest difficulty I got lots of black cards with no swamps at all. I threw out trash and ended up with about 30 cards. But during battles i get hand full of swamps and mountains (I have two mountains but they're not in my deck). Does game automatically complete my hand to 40 cards with some random basic lands or is it a bug? Can I get swamps this way and bring my deck to two colours (now there are only green and few white cards).

Yes, I think you get random basic lands so the deck fills up to 40 cards.