The best name for the card would be Scavenge, although that's already taken by the vulture's skill "scavenger."
"Snatch" is kinda taken by "Steal", though, so the same can be said about the current name. <.<
I like it a lot but should it be cheaper? isnt mindgate 5 and 4 and it can steal cards every turn without the 2 card combo
It's already pretty cheap. Mindgate's cost is 9 or 8 (5 or 4, ability costs of abilities used each turn count twice so +4).
This is 4 or 3 (5 or 4, quanta gained from situational triggers only count once so -1).
However, I agree, since it has a limited amount of uses (6, nightmare + silence chain) and multiple copies of it can clog your hand. In addition, nightmare might not even force the opponent to discard, since most pillar-based decks have enough quanta to play the cards that were originally in the hand.