Preventing your opponents from splitting their forces can be quite effective, especially since so many Commander players prefer to split the love across the table
There's a wide variety of instants, sorceries, and even cards that interact with a few specific mechanics that will help you get ahead in card advantage, the iconic concept Magic: The Gathering players constantly look for
Promo 151/XY-P - Gyarados Poncho Pikachu 51
While Wort, the Raidmother and Djinn Illuminatus are nice copy spell reprints, the coolest is Charmbreaker Devils
Sometimes the only good bug is a red bug
Mostly due to early templating and designers not realizing what they were doing rules-wise, Urza's MineUrza's Mine, Urza's Power PlantUrza's Power Plant, and Urza's TowerUrza's Tower have the land types "Urza's Mine", "Urza's Power-Plant", and "Urza's Tower"