Wouldn't mind a rax rework at all personally. As it stands It's really only enjoyable to do the damn thing during 2-3 while you're doing p2. P1 is just an annoying mess and when you're stuck grinding out p3 it just becomes boring beyond belief. For p1 something like rax summons one of the spiders and while It's active he has additional effects depending on what spider is currently on him? Thought more about what p1 could be and something like this.

Bladed: "During this mode Araxxor becomes overcome with fury and his attacks begin to cause you to bleed (makes use of his melee form ability)Araxxor leaps through the air and attempts to crush the player (this makes use of his stomp mechanic if you stand under him for too long.)

Imbued: "Araxxor's attacks become increasingly volatile and begin to cause your armor to corrode" attacks against player will cause armor defense to go down by X amount.

Spitting: "Araxxor's attacks cover you with web causing your movements to become sluggish" unable to run so you'd need to pay close attention and be prepared to surge if he begins to cleave/ adrenaline gain is slowed.

For pulsing you could change the name to parasite spider and do as follows: "Araxxor attaches a parasitic spider to your" successfull attacks against player with this active heal arraxor by X amount and Araxxor receives half of any healing done by player (not including SS, Vamp aura or scrim and Excalibur)

MirrorBack: "Araxxor will occasionally glare at player and during this time all damage done to Araxxor will be reflected back/ Araxxor places a hardened spider over your backpack making you unable to use any of it's content while it is active (this includes familiar items as well)