these (roughly) indicate the monster's relative power, and whether it needs Tributes to be played
Most only use materials from 1 location (usually field)
Plus, [c]Teferi, Time Raveler[/c] gives your sorcery spells flash as his +1 ability
Roar of the Blue-Eyed Dragons X SPELL Special Summon in Defense Position, 1 "Blue-Eyes" monster from your Deck, GY, or banishment (but if you control no "Blue-Eyes White Dragon", you can only Special Summon "Blue-Eyes White Dragon" with this effect), also you cannot Special Summon from the Extra Deck for the rest of this turn, except Dragon monsters
A card like Ignis Scientia will allow you to put another land onto the battlefield, and because it doesn't specify that it needs to be a Basic land, you can play something more powerful, like one of Final Fantasy 's towns
In fact, its the opposite: theyre all efficient, popular staples played often in Commander