Sweep Sweep was an ability word from Saviors of Kamigawa on instants and one sorcery where you could return basic lands of the appropriate type to your hand to determine how big the effect of the spell was
Theyre balanced against each other so you and your friends can pick them up and start battling each other right away
I even love the clunky combat tricks that just play weirdly, like [casthaven]Swell of Growth[/casthaven] (it was supposed to provide an additional buff to landfall creatures, but the rarity of that being useful, due to the low power of landfall creatures, often relegated it to a horrible ramp spell)
This set drastically lowered the barrier to entry for competitive play by re-introducing hard-to-find, expensive staples (like the 10-cost Doflamingo and Katakuri) back into the market in massive numbers
There are other decks sprinkled in as well that make up a more minor part of the metagame, like Golgari Midrange and Esper/Azorius Mentor, but overall these are the core strategies of the current Standard environment