If you had an Alpha card with a base buy price of $25 and it was graded down to EX, you would receive $20 for the card, or 80%
Once it hits the field, it deters opponent's from attacking you, as all your creatures will have double power and toughness for every combat phase, not just your own
If Gisela does see a lot of play, it will be with Bruna, the Fading Light and not on her own
In particular with Deathrite Shaman, the presence of fetchlands in Modern and Legacy made it way too efficient at providing mana on Turn 2 whilst also breaking the colour pie since you could cast this particular mana creature with black mana
Value of non-Alpha are about $3,200
The truly hungry frog munches on your mana sources, but lets you spit them out from your hand at twice the rate as normal