Sources: TCG Player (Base Set Mewtwo, First Edition Rocket's Mewtwo, Mew & Mewtwo GX, Mewtwo ex, Mewtwo Gold Star, Rocket's Mewtwo ex, Shining Mewtwo, Mewtwo e-Card, Rocket's Mewtwo [Winner], Mewtwo [XY Evolutions Staff Prerelease]), PriceCharting (Base Set 1st Edition Shadowless Holo Mewtwo, Mewtwo Gold Star)
#19 This is cool, but it also seems a bit gimmicky
It asks for minimum effort for maximal output, and its usually safer in the bin than a permanent on the battlefield would be
Its very hard to start the game without a plan to get to six mana, so keeping an opening hand with two or more mana rocks is usually best
If it wasn't land, you gain two life and deal two damage to each opponent
Spells like Temporal Trespass and Dig Through Time benefit from delve, offering powerful effects at a reduced mana cost