All of the foils are equal in rarity, so the rare and mythic rare foils are naturally devalued because their rarity symbols dont matter
So with all of the explanations out of the way, lets get into it
It is important to note that even the best burn spells MTG are not always the most effective way to deal with a situation
You can also use cards like Ram Through to push Omanths damage through or equipment like Forebears Blade to give it trample Purphoros, God of the Forge & Arasta of the Endless Web There are plenty of wild things you can do with Purphoros, God of the Forge which can help whittle your opponents life totals away
This was especially true in Commander, where the lack of sideboards meant the mechanical pairing didn't work, and the Lessons were too weak and under-supported to justify playing
Of course, this card lends itself better to decks that go wide, but even if youre not planning on attacking with a wide board of creatures, Proliferate can still do a ton of work