If its the magnet plant that makes enemy bullets not move, thats because it has 2 attributes, one that increases the distance from which hearts and golds are pulled towards the players and the second one, that is supposed to work against enemy bullets, it literally says "repel pest shots", that sentence used to mean nothing, now it works, the problem is, that its way too strong.
If it only decreased the speed of enemy shots to some degree every time when picked up, instead of fully negating it, it would be a good item.