Dryad of the Ilysian Grove and Imprisoned in the moon

Question

Following on from this conversation, what happens if we replace Icthyomorphosis with Imprisoned in the Moon in that scenario?

I think:

1. All Lands become all basic land types
2. Dryad of the Ilysian Grove becomes a land and loses all other types.
3. Dryad gains all basic land types to its own ability, then loses them again from Imprisoned in the Moon, due to timestamp order.
4. Layer 6 removes all abilities from Dryad, including any mana abilities it may have inherited from becoming all basic land types (although, as it had already resolved as non-basic in layer 4, I'm not sure that's even relevant, as it wouldn't have received those mana abilities until layer 6 anyway), and adds "t: add colourless"

Answer 1

Your description has the correct result. This looks like the interaction with Magus of the Moon.

The steps are different though. 1. In the layer 4, Dryad becomes a land. Then its ability gives it all basic lands types (and the associated mana abilities). Dryad's ability is applicated second because it depends on Imprisoned's one. 2. In the layer 6, Dryad loses its printed abilities and its additional mana abilities but gains "{T}: Add colourless".

No timestamp order is involved. As a bonus, if you care about land types, Dryad still has all of them.