This build technically requires only 3 formas as 2 of the ones listed above are from the selected mutagen and gilding.

Vupaphylas cant be revived as long as they have their Devolution precepts installed. Instead, they will become a sentinel with just 1 health and max amount of shields for 30 seconds, after which they come back as normal pets.
For the time being, they can't be killed in their sentinel form, although their shields can be damaged. After dying many times they also get back to lvl 0, keeping its old mods but losing any other benefits from being on a higher level such as health, armor and shield increase (they get back to their original level after the mission so you don't have to worry about leveling it up again and again).

Because we're not focusing on the damage dealt but rather the viral procs and just the base damage over time, we don't need any mods affecting damage. [Viral Quills] has a cooldown of 4 seconds and has a 40% chance to proc a viral status making it proc the spores very often by itself and makes viral procs from any other source unnecessary.

[Viral Quills] has a strong synergy with both [Hunter Recovery] and [Synth Deconstruct] granting you healing over time and more health orbs from enemies.
[Synth Deconstruct] has a great synergy with [Synth Fiber] allowing your pet for massive armor increase very often.

[Primed Pack Leader] is a flexible slot and can be swapped for any utility mod as well as Link Shields and [Maul].