Repudiate
{G/U}{G/U}Instant
Counter target activated or triggered ability. (Mana abilities can't be targeted.)
Repudiate // Replicate
{G/U}{G/U} // {1}{G}{U}
Instant // Sorcery
Oracle Text
Replicate
{1}{G}{U}Sorcery
Create a token that's a copy of target creature you control.