Songhai, especially slower control variants much like the one im using often find their spells to be overcosted or clunky on their curve. While it is true that Vortex, in a vacuum produces a net loss in terms of card advantage, it also counteracts that by functionally smoothening out and lowering your spell curve, a effect which when built around simply cannot be overstated,
Take a conventional approach to say a Spear based control list, now lets add in the traditional package of Twin Strike, Ghost Lightning, 4 winds, OBS, maybe a Cobra Strike or two. Already we start to see a problem here, these types of spells are not only situational but they often take up enough mana to the effect of using most of your resources for that turn but lets be a little bit creative here.
When tossing Vortex, a relatively inefficient card as discussed, in to the mix, interesting plays start becoming possible that previously were limiting deckbuilding. As p1 on t2 you can Vortex and Cobra to eat their 2 drop and push damage. On 5 mana you can OBS + Twin Strike to clear most boards without losing tempo. On 6/7 mana you start being able to use HE to draw turns earlier than you normally would have, and making far more powerful tempo plays and none of this takes into account what sort of deck youāre playing in terms of support card.
4 Winds, Archanysts, maybe a more aggressive spellhai variant with Blood rage Mask, all things that can benefit not only simply from triggers but from the sort of tempo plays that Vortex enables that otherwise might have been too slow or at too mana inefficient spots on your curve.
This is not to say Iām stating Vortex is this super powerful card and most are wrong not to run it, but rather that there is far more nuance to it than most give it credit for and a good deal of sysnergy and unexplored decks to be made available in no small part due to āunplayableā cards such as Mana Vortex.
I hope this gives you a small insight into the rambling mess that is my mind but itās definitely a concept Iāll be pushing and exploring more myself in the time to come.
PS: Next up, why Kaleos is a better controlling general than Reva and how most players use him wrong 