You need to operate at sorcery speed for this to be effective
Samut takes full advantage of this, granting other creatures the player controls +X/+0, where X is their current speed, as well as making non-creature spells cost X less to cast, where X is their current speed
Youll still want a nice bell curve of mana costs in your cards, but unless youre playing cEDH (competitive EDH, a hellscape where games end before youve even finished shuffling - fun, but in a horribly different way), you can have a bit more fun
The card will also be fine in casual Commander decks where its three mana cost isnt too restrictive, and could have further versatility in strategies that can reliably pay both costs for the card, like Jodah, the Unifier
Why buy copies of Dark Banishing if you can go can purchase copies of Doom Blade or Murder instead
There's plenty of ways to get lots of artifacts out and pump this guy, but this is like the same as another card in this set, basically 2/2 for 3 with an ability that gives it counters and basic evasion, which is pretty same-y