La créature ne peut pas bloquer.

"Cette créature ne peut pas bloquer", ça ne rentre pas dans "perform any action" - ça serait le cas avec Incremental Blight et une des cibles qui acquerrait protection contre le noir.
Ça ne rentre pas dans "make another object or player perform any actions on that target". Exemple : Reweave splice sur Glacial Ray et la créature ciblée par la partie "Reweave" acquiert protection contre le rouge.
Et pas non plus "make that target perform any actions" comme dans le cas d'un Soul's Fire si la créature acquiert protection contre le rouge.

La réponse que j'ai apportée vient d'une source officielle et fait foi.[...]
On peut penser que cette règle est mal fichue, mais en tout cas, on ne peut pas la contredire.

La source officielle qui a rendu la réponse que j'ai fournie est déjà en train de s'occuper d'un traitement de ce cas.

If the spell or ability specifies targets, it checks whether the targets are still legal. A target that's no longer in the zone it was in when it was targeted is illegal. Other changes to the game state may cause a target to no longer be legal; for example, its characteristics may have changed or an effect may have changed the text of the spell. If the source of an ability has left the zone it was in, its last known information is used during this process. If all its targets, for every instance of the word "target," are now illegal, the spell or ability doesn't resolve. It's removed from the stack and, if it's a spell, put into its owner's graveyard. Otherwise, the spell or ability will resolve normally. Illegal targets, if any, won't be affected by parts of a resolving spell's effect for which they're illegal. Other parts of the effect for which those targets are not illegal may still affect them. If the spell or ability creates any continuous effects that affect game rules (see rule 613.10), those effects don't apply to illegal targets. If part of the effect requires information about an illegal target, it fails to determine any such information. Any part of the effect that requires that information won't happen.

608.2b

This rule talk about how a resolving spell or ability checks to see if its targets are still legal. If a spell or ability has multiple targets, it can still resolve as long as at least one of its targets is still legal. Here's where it gets fun. The rule specified that the spell or ability couldn't perform any actions on an illegal target, make that target perform any actions, or make another object perform any actions on the illegal target. This was a technical way of saying that illegal targets aren't affected by spells and abilities.

But there was a problem: spells and abilities could affect an illegal target without performing any actions. Consider Frost Breath. If one of its targets was illegal when it resolves, both creatures wouldn't untap during their controller's next untap step. This feels very wrong, so when Sudden Storm appeared in the Born of the Gods set, it seemed like a great time to address it. The change to this rule shuts down this hole. Illegal targets of Sudden Storm (and Frost Breath) won't be affected and will untap as normal.