This is certainly an interesting card, but it seems too situational. Purify has healing built in so that it's not utterly useless against non-poison decks.
Thought about that too. Any suggestions?
I think this card should be ok in this respect. Purify definitely needed the healing aspect to make it useful because you are not guaranteed to be fighting a deck that uses poison.
This card, on the other hand, belongs to an element which makes heavy use of poison. Therefore, you have good control over whether or not there will be a valid target.
E.g. You can use this in conjunction with aflatoxin, virus, deadly poison, etc.
There are enough cards in the game that allow you to inflict poison so that it shouldn't have any problems with being situational.
It should be noted, however, that this card will generally be less powerful than plague in most cases. The reason is that it requires a lot of effort to poison a given target to begin with. So as a means of distributing a lot of poison at once, plague is a much better choice.
Where this card really shines is that it has more flexibility in its utility.
For instance, like purifiy, it can be used defensively to cleanse a target of poison.
It can also be used to reassign poison from a target that is about to die
E.g. if you pumped 5 poison into an armagio and it is down to its last hp, you can spread it out so that the poison won't be lost.