I think its pretty clear that the card is a little weak and slow for Vintage Cube, but it does give you four effects that are worth at least half a card
Sure, Giratina VSTAR is powerful, but without Mirage Gate, it would be impossible to use its Lost Impact attack properly
As much as people long for the good ol' days of Splinter Twin Modern, in reality, most people wouldn't be happy with a Modern format where they played Twin all the time
Here is the thing: while Unstable has a ton of splashy, crazy cards and mondo-combos, down in the weeds there are all sorts of neat little synergies you can tap into to gain an edge
Neo Genesis revolutionized the games core mechanics by introducing Darkness and Metal types, complete with Special Energy cards