Talk about Myxomycetes.

Simplest, Thallus consists of mobile multinucleated mass called plasmodium or plasmodial slime mold, crowls like amobae, coenocytic mass without cell wall and multinucleated, mostly diploid. Saprophytes plasmodia feed by phagocytosis and live on damp substances (leaf litter and decaying wood). Some are plant parasitic.