Rituel
Choisissez une créature ciblée que vous contrôlez et une créature ciblée que vous ne contrôlez pas. La créature que vous contrôlez gagne +2/+1 jusqu'à la fin du tour si c'est un chevalier. Puis, ces créatures se battent l'une contre l'autre. (Chacune inflige un nombre de blessures égal à sa force à l'autre.)
If the creature you control is an illegal target as Joust tries to resolve, no creature gets +2/+1. If that creature is a legal target but the creature you don't control isn't, it still gets +2/+1 until end of turn if it's a Knight.
You can't cast Joust unless you choose both a creature you control and a creature you don't control as targets.
The target creature you control gets +2/+1 only if it's a Knight as Joust resolves. It'll still fight if it doesn't get +2/+1.
If either target is an illegal target as Joust tries to resolve, neither creature will deal or be dealt damage.