Probably a Slime Mold
Slime molds are usually harmless. It's the black jellies you have to look out for they are huge and flesh eating.
Strange... Never even heard of a slime mold before.;
Also Palla that sounds.... terrifying. D:
If slime mold gets inside your air conditioning, you've had it.
(And it isn't sap right?)Does it look like this? http://i.imgur.com/Ij4pDgg.jpg
I would ready to roll for initiative, just in case. On a serious note, I don't think it is harmful, but I still wouldn't want to breathe in its spores.
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