However, removing a single thing while not having complete control over what you remove is probably still going to be situational
For instance, I took Electabuzz's Light Screen and taught it Butterfree
You ideally want to be a little ahead or at least have multiple ways to deal with any given problem available to you so you are never forced into trading your Counterspell for a weak card
Fires of Yavimaya Much has been said on this subject
You might remember a few months ago when I suggested opening a TCGplayer seller account (which I still recommend doing), but for the purposes of checking the last sold listing measurement tool to gauge whether there was real demand for a card
18 Samut, Voice Of Dissent Jam As Many Keywords As You Can A great option for an aggressive Naya deck, Samut may appear to be Gruul at first glance, but her white activated ability allows her to be played as a Naya commander