Two years later, he forced the Patriarch of Aquileia to flee to Venice and then obtained from him the title of capitano generale of Friuli.
Seeing his eastwards expansion had failed, he sided with the Ghibelline party, gaining from emperor Henry VII the title of Imperial Vicar.
However, this deprived him of the support of the Venetian doge and of the traditionally Guelph Trevisan nobility.
On April 5, 1312, while playing chess, Rizzardo was fatally wounded in the loggia of his palace.
Other sources call in the Paduan nobility, the Veronese leader Cangrande I della Scala or even his brother and successor, Guecellone VII da Camino.