TL ; DR: Consider going into every map and hiding Sunflowers near every tombstone (if possible) to counteract the Graveyard minibiome introduced in Journey’s End for visibility purposes once the server fully updates to 1.4. During Halloween event periods on Zombies, the Sunflowers could be removed from the maps to better fit the event theme of sp00kiness.
As of Journey’s End, if several tombstones are in close proximity, a Graveyard minibiome begins to show up. The presence of the biome is indicated by the game screen beginning to lose saturation, and Ecto Mist lingering in the area. Natural enemy spawns appear to be blocked in Zombies, so the extra enemies that appear in Graveyards in normal play shouldn’t pose a problem in Zombies. However, what would pose a problem are the visual effects from being in a Graveyard minibiome, since enemy spawn locations are marked with tombstones. The aforementioned biome presence indicators could cause hindrances, such as every chest looking mostly the same (even with paint), enemies being harder to see (losing color in dark areas and potentially blending in to their surroundings), or straight up hiding the enemies in Ecto Mist.
Currently, it takes 4 tombstones in one area for that area to count as a Graveyard. Given how some maps aren’t very large, that could mean the entire map is registered as a Graveyard. However, as of current, for every Sunflower there is in the area, one tombstone will be counteracted in formation of a Graveyard. (e.g. 5 tombstones and 1 Sunflower in an area means that the game counts them as the bare minimum of 4 tombstones being present for a Graveyard. For future reference, I’ll refer to this as the tombstone threshold.). It may stick out from the rest of the theme of the map, but a potential workaround is to hide the Sunflower in an inaccessible area (e.g. in a wall at the map border, underneath the floor, or in the ceiling) and make sure there is no other light intruding by covering the area behind the Sunflower with background walls. Then, by painting the Sunflower, its grass blocks, and the background walls, it could be very well hidden away, with the only visual downside being the minor glow the Sunflowers produce. However, the small downside of using Sunflowers means that the Happy! buff that Sunflowers apply to players within 50 tiles of them will always be active on the map unless there are enough tombstones over Sunflowers (hidden or not) to reach the tombstone threshold and create a Graveyard on the map, meaning that there would be some slight desaturation of the map overall. Maybe leave it up to the map creators if they want to update their maps to have Sunflowers in places to counteract Graveyard formation. Or it could be done manually for every map…
At Halloween, the time of the year that’s typically associated with fright, more tombstones could be added around to maps, except hidden away and unable to spawn enemies. This way, more of the map converts into a Graveyard biome to fully swing into the theme of Halloween, as the mist and desaturation of colors are typically associated with the spooky time.
To summarize my """"solution"""" of adding hidden Sunflowers to maps:
Pros: no Graveyard biomes, vision of both enemies and map geometry is clear
Cons: Happy! buff would apply everywhere on maps unless a minimum Graveyard is made to be everywhere to counteract it