Artistic Refusal

Because convoke isn't an alternative cost, it can be used in conjunction with alternative costs.

Tapping an untapped creature that's attacking or blocking to convoke a spell won't cause that creature to stop attacking or blocking.

When calculating a spell's total cost, include any alternative costs, additional costs, or anything else that increases or reduces the cost to cast the spell. Convoke applies after the total cost is calculated. Convoke doesn't change a spell's mana cost or mana value.

If you choose both modes, and the target of the first mode is an illegal target at the time Artistic Refusal tries to resolve (probably because that spell has been countered by something else), Artistic Refusal won't resolve and none of its effects will happen. You won't draw or discard any cards.