Mythic Rares were introduced in the Shards of Alara block in 2008, and have had a dramatic impact on the financial landscape of the game, draining value from the lower rarities in much the same way that Expeditions (Battle for Zendikar/Oath of the Gatewatch) and Masterpieces (Kaladesh) do to the expected value of booster packs in their respective sets
This might be the ultimate example of flexible graveyard hate and a worthy inclusion in any controlling deck interested in resetting the game
Or you can make a one of 3/2 Horse named Phobos which is legendary, so just one at a time
We've seen good examples of this over the past couple of summers, where the summer creates a hole in the schedule for those who aren't interested in Limited formats of the summer set or in Alchemy
This comes in spite of the fact that there are 118 non-foil, near-mint listings still available for MTG Foundations copies
Not once per turn, no reset on damage, just once