There are also platforms online that can give you an estimate of the value of your card
Since Gardevoir's Ability is so important I would definitely recommend keeping Gardevoir on the bench at all times, since it only has 110 hp, you need to prevent Gardevoir from getting much damage on it and thus getting knocked out
Dark Ritual became so damaging to the design process of black spells that Wizards R&D phased it out of the main set, the DCI banned it from Extended, and players all across the world rejoiced or sobbed, depending on how much of a black mage each was at heart
While it shines in formats with fetch lands, its generally powerful everywhere
The Goblinsons may be a tiny 1/1 at first, but left unchecked, it grows into a massive trampling problem for your opponents
What I feel happened was there was a coordinated move to buy up all the supply under around 200 dollars on this card over the period of a couple of days, moving the price point of the card to unheard of levels