Sometimes the best way to keep games fresh is to change up the formats some, and Magic: the Gathering has been around for many years. I remember when I started playing, way back in the mid to late 90s, and to be honest, the core game has changed very little since then. Since then, many variants have come about that change that core game to something different so to keep the people playing.
Several formats have come about, some fan made, some official. Some examples are EDH (Elder Dragon Highlander, later released officially as Commander), Planechase, Peasant, Two-Headed Giant and Emperor. One more recent one to come from Wizards of the Coast is Tom LaPille’s Cube. And now a new one has come up, Wizards Tower.
The premise of it seems pretty simple, you shuffle together 9 booster packs with 80 basic lands and then everyone uses that same deck as a library and the graveyard is shared too. There are a few more details to it than that as well, so if it so far sounds interesting, then go over to here to look up the page with the rules on it.