He's not op!
Jugg is good only if ramped out,
When ramped uses 3 cards, 2 of them are missed makantors
It's incredibly weak to lightbender: you use 3 cards to get a 4/6
If played on curve:
Case a: you are already winning and don't need it.
Case b: you are losing and this won't help your board.
Case c: the game is stalled, usefulness depends on your opponent removal option and deck.
"If unanswered you lose" like a lot of other cards, the only difference is that sometimes the others are cheaper.