Creature with negative attack

[mesaprotector]

I'm sure something like this has been thought of before, but I couldn't find it, so:

Name: Compassionate Spirit | Loving Spirit
Stats: -2|3 | -3|3
Cost: Free
Immaterial. Gain 5 | 7 when this card is played.

Basically a card which gives you rushing power, but at the cost of healing your opponent. I'm trying to come up with a way to make it combo with a few more cards (one of which is not Immo :/ )

[Shylderidh]

I had an idea like that.

Traitorious healer  (cost   )
-3|2
Passive : Healer, heals two random injured creature of his side of 1hp each turn*
Ability : Change Side (becomes an opponent's creature)

* this passive is optionnal, but I found good to give him an use if you keep him in your side ; makes him usable to counter damage shields at the price of healing your opponent or usable to heal you at the price of healing opponents creature