Est ce qu'on peut rediriger des pertes de point de vie sur un PW. Avec un Hideous End ou la grosse créature black qui faire perdre 3 pv qd elle landfall ?

Non, ca ne marche pas. Seul le non-combat damage peut etre redirige vers un PW.

306.7. If noncombat damage would be dealt to a player by a source controlled by an opponent, that opponent may have that source deal that damage to a planeswalker the first player controls instead. This is a redirection effect (see rule 614.9) and is subject to the normal rules for ordering replacement effects (see rule 616). The opponent chooses whether to redirect the damage as the redirection effect is applied.

Merci, Dave, j'étais plus sûr....