For those curious, Mycella has the following features:
Heroic
271 HP, 905 SP
Spore aura- +4 to hit, +2 to will saves (may not stack with other bonuses)
Damage numbers in the high 30s with staff.
Hotbar:
1. True Seeing
2. Healing Spores (costs 40 sp, seems to be an AoE effect- looks 60 healing per tick before healing amp, ticks every couple seconds)
3. Cure Serious Wounds
4. Reincarnate
Legendary
2243 HP, 3270 SP
Spore aura- +8 to hit, +4 to will saves (may not stack with other bonuses)
Damage numbers slightly above 600 with staff.
Hotbar:
1. True Seeing
2. Healing Spores (costs 34 sp, 205 healing per tick minimum but saw a lot more high ticks, so either rather high spell crit rate or it's more variable than the heroic version)
3. Heal
4. Reincarnate
Those are all baseline numbers, no druid past lives, augment summoning, or ED bonuses. Didn't run through tests to see how "survivable" they are but I could see the heroic version running through SP a bit quickly because it wants to use fire seeds which is a major waste of SP given how often it just doesn't hit anything. I subtracted my healing amp (healing received divided by 100+hamp * 100) to get the healing number.
That said, the healing is pretty fast and is an AoE so it will be putting it on all melee friends hitting the same target, and it does have a damage over time component that... really didn't seem very good in legendary (around 350?). I think the heroic version of Mycella is definitely sufficient for healing, but I'm also a little worried that Mycella will zerg in, pull aggro, and die. Both versions of Mycella seem to have decent healing amp, so in theory they would be fine until they run out of SP, which will happen somewhat quickly in heroic based on the spell costs especially when the melee druid decides to spam fire seeds that don't even spawn in.
Spell selection is a bit disappointing. Rana 2.0 right after the expansion where we got Rana. Would like to see a different spell list beyond the unique myconid ability since the two of them sit right next to each other in level range. They literally have "true seeing, heal over time, healing spell, and reincarnate" so like... yeah, they basically have the same spells. The spore aura is nice, but I have a feeling the spore aura will end when Mycella inevitably dies. All soul stones are functionally identical, so Rana is probably the "better" hireling for survival reasons alone. Though those healing spores are pretty nice in heroic.
Spotted some typos in the Telepathic Spores description- coordinate misspelled as cordinate, permanent is misspelled as permenant, and the last phrase is grammatically odd.
Mycella is listed as male in game but Torc said Mycella is a she. Myconids are canonically sexless so it doesn't matter, but it is inconsistent.
Fire Seed still doesn't consistently proc, especially while in melee with a target. Putting it on a melee druid is a waste of SP.