One of the limitations of using Wild Shape is that, in most beast forms, a druid cannot talk, as per the PHB:
You can’t cast spells, and your ability to speak or take any action that requires hands is limited to the capabilities of your beast form. (my emphasis)
One of the key benefits of Wild Shape is scouting ahead for the party, and it turns out the Cranium Rat (from Volo's Guide to Monsters) is ideal for this:
- Rats are commonplace creature in many towns or dungeons, and are therefore less prone to generate suspicions even if detected.
- Darkvision is a benefit in dark places.
- No extra Stealth bonus, but +2 from DEX is still a bonus.
- Telepathic Shroud makes it immune to emotion-sensing, mind-reading and divination spells.
Many animal shapes have great scouting abilities, but the Cranium Rat even has the ability to use Telepathy for up to 30ft, potentially allowing the druid to communicate secretly with the party, relaying information about what it sees.
I'm still baffled that the Cranium Rat is categorized as a beast, and not as a monster of some kind, but it's a beast per the RAW. Since the Telepathy ability of the Cranium Rat is a "capability of the beast form", does this mean that a druid can indeed use Telepathy when transformed into a Cranium Rat?