Varicella is a 1999 work of interactive fiction by Adam Cadre, distributed in z-code format as freeware.

It is set in an alternate history which features roughly modern technology mixed with Renaissance-style principalities and court politics.

The player character is Primo Varicella, palace minister in Piedmont, who has to get rid of several rivals for the regency following the death of the king.

He was inspired by the Machiavellian protagonist of Profit, but given even more despicable antagonists (just as variola is more virulent than varicella), thus making players willing to go along with his schemes.

[1] The international situation in the game is described in passing: Piedmont is part of a loose confederation of kingdoms that make up a Carolingian League and is engaged in a war against the Republic of Venice.