At the back of the Tomb of Annihilation book, in Appendix B, there is a random encounters table for Wilderness Encounters on pp. 194-195. The different terrains listed in that table are as follows:
- Jungle; further divided into:
- No Undead
- Lesser Undead
- Greater Undead
So that's 9 different terrains in total.
Looking at the map on p. 39, there doesn't appear to be any legend for describing the different terrains. The only key is as follows, and only shows what the lesser and greater Undead territories look like*:
The only descriptions I can find in the books are on p. 38, which lists the different terrains under the Travel Distances and Navigation sections but does not expand on how to identify these areas on the map, and on p. 40, which is just the section Undead Territory, which only explains the undead territory as per the above key.
The description of the random encounter table, Wilderness Encounters, only says: "Roll percentile dice and check the Wilderness Encounters table for the terrain appropriate to where the characters are", without actually elaborating on how to determine that.
From the map itself, a lot of it is obvious; where the map shows a lot of trees, clearly that's Jungle, and for hexes that intersect mountains, clearly that's Mountain, etc. However, Ruins, Swamp and Wasteland are quite ambiguous to me with only the map to go on.
So is there any way to determine these terrains besides just eyeballing the map, and how am I supposed to identify Ruins, Swamp, or Wasteland from the map (if eyeballing really is the only way)?
* There's also "Ruin" included in the Key, but I assume this is the location of a specific ruin rather than denoting that it's a type of terrain, especially given that the black square icon turns up in different terrains (for example, the Orolunga ruin is clearly in a hex of Jungle terrain), so I am unconvinced that the black square icon for "Ruin" is related to the "Ruins" terrain.
Below I have attempted to identify each of the 9 different terrains from the map, as well as my best guess as to what they are (some are obvious, others less so, hence my question):
- Beach, because it's next to the water, this makes sense to me.
- River, because that hex contains a river running through it.
- Jungle, clearly, as it's all trees; specifically, "No Undead" Jungle.
- Jungle, Lesser Undead, due to the light yellow colour coding and the black skull and crossbones.
- Jungle, Greater Undead, due to the dark yellow colour coding and the red skull and crossbones.
- Mountain, because this hex is well within the mountains.
- Maybe Swamp? It looks kinda watery, and it is near water (the river in this case), but isn't actually water, so that's my best guess...
- This could be anything, the round shapes could be Swamp-like areas, or is that supposed to be Ruins? They don't look much like ruins to me.
- This isn't Mountain, because 6. is Mountain, so I guess this must be Wasteland?