Bloaters are the fourth, rarest, and most dangerous stage of the Infected, taking several years to develop and reach this stage after years of exposure to the Cordyceps Brain Infection. Furthermore, Bloaters are incredibly strong and are covered in thick fungus that effectively acts as armor plates. Therefore, their skin forms large patches of scale-like tissue that glow in the dark, which form their mycotoxin pouches and engulfs their entire body that they use as a long-ranged weapon, replacing the warden's sonic explosion attack.
Like Sculk would, this cordyceps fungus will grow in size and spread when a mob dies on it, mimicking a fungal infestation, and creating large networks that are menacing in look.
Sculk Catalyst > Fungal Catalyst
This new and improved catalyst will consume organic matter greatly increasing its size while having a detailed particle animation.
Sculk Shrieker > Puffball Mushroom Spore
This mushroom is similar to a real-life fungus called "Puffball". It opens a hole where it will release spore particles alerting a bloater.
Sculk Sensor > Cordyceps
Similarly, to the cordyceps in, "The Last of Us" series for HBO, they create large networks of cordyceps tendrils. When it senses movement, the cordyceps tendrils begin to thrash around, alerting the nearest mushroom spore.
Calibrated Sculk Sensor > Calibrated Cordyceps
Basically, buffed sculk sensor for redstone.
Sculk Vein > Cordyceps Tendrils
This block appears to spread fungal tendrils, using it as a substrate feeding off of its nutrients to further advance its infection of the world.