When is a mushroom not a mushroom?
It looks like a mushroom, smells like a mushroom, lives it’s life in the way that a mushroom does. But uproot this super-rapid breeder and you’ll see tentacles, not roots. Oh yes, this mushroom is actually an animal that barely does anything. That’s cool I guess.
Doesn’t really do much for us in a Dungeons & Dragons campaign, but hey, we’re making them all.
Horklump

So the Horklump is doing absolutely nothing for us in a combat encounter, but there is something very odd that creeps in when you make a monster that’s an animal that thinks its a plant.
There are spells that allow you to interact with plants. You can chat to them, make them grow quicker, even teleport through trees. So straight away there’s chance that a druid is going to think that the Horklump is ignoring its attempts to interact with them, getting slowly more annoyed by a fungus.
Then there are the spells that allow you to interact with the ‘beast’ type of monsters. The Horklump might have “no discernible use” according to Fantastic Beasts, but in D&D these little puffballs might have a time to shine.
Speak with animals is a lower level spell that speak with plants, so a knowledgeable caster will know that chatting with a nearby Horklump makes ‘more sense’. You could cast conjure animals and summon 8 Horklumps. I… don’t know why you would do that. Mad at your neighbour?
Most interestingly, beast bond allows you connect telepathically with a beast and send simple, conceptual messages to each other. When you consider that most creatures won’t think twice about a clump of mushrooms, and you have yourself an excellent early warning system when you are camping. Pot a clump of Horklump and take it with you, and their blindsight will allow you to detect when invisible creatures are nearby.
You’ll look looney, walking around with a handful of mushrooms, but that’s a small price to pay.
Thank You For Reading
You cand more D&D-readied Fantastic Beasts right here!