by s3kt0r
Sounds like preconstructed decks from the Onslaught block, so that's good for playing because they should already be built to play with without you having to know how to build a deck.The wording might be a little off from modern cards, but you could definitely start by running through the tutorial on Arena and then start playing with the decks you have. You'll probably run across a lot of questions about certain keywords, but I think that was a tribal block, so it shouldn't be too complicated. As always, you can ask rules questions here.
Oh, and I was mostly joking about the Black Lotus. The odds of it being in with those cards are exceedingly rare.
https://www.cardkingdom.com/mtg-sealed/scourge-theme-deck-pu...
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https://www.cardkingdom.com/mtg-sealed/scourge-theme-deck-go...