Hey, it's up!
Viruses cost 1
![Death :death](https://elementscommunity.org/forum/Smileys/solosmileys/../../../images/Misc/death18x18.png)
, so it's Retrovirus that you're thinking about. But considering how easily it can be felled by CC, I think that 2
![Entropy :entropy](https://elementscommunity.org/forum/Smileys/solosmileys/../../../images/Misc/entropy18x18.png)
, or maybe even 1, would be a fine considering how, aside from OTK decks or shield chains, this can't really affect the game too badly.