It's a shame they're MtG creatures, because the small cackler demons from Guildmaster's Guide to Ravnica could really fill the goblin niche.
I could see these guys as replacements for the Pathfinder 1E style of goblin that sings gleefully about killing dogs and eating babies.
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They have the Mimicry trait to mimic sounds and voices, so they could lay ambushes by mimicking past victims' cries for help or whatever. They also have Tasha's Hideous Laughter once per day, which is also good for incapacitating victims and forcing them to laugh as they get chopped down.