Mobile Having trouble to get lightning bugs, here is how.

[Sirine]

1) Put 1 row of dirt. (101 blocks. Above or at surface)
2) Use Hallow Seeds to create Hallow biome. (Plant some tree, if you like)
3) Build a valid small 6x10 house on 2/3 of the row.
4) Put King or Queens or both statue in the house.
5) Block the door with wood wall. (No connection - Not touching the house) So, NPC will not be able to walk out the house.
6) Put grey plate outside the house, wired to the statue(s).
7) Wait till night. Step on the grey plate to teleport NPC in the house.
8) The house preferabaly already occupied with an NPC.
9) Make sure there are 3+ NPC in the house, walk slowly away from the house.
10) The lightning bugs should spawns...lots of them.
11) NPC will despawn and back to their house if out of your play screen.
12) Just keep teleport them back with steping the grey plate. (Repeat step 9)

 

[ps3wolvrine14]

You should post a screen shot. I'm gonna try this tho cause i can't get those ers. Any idea if sunflowers help?
Also i advise adding a underboarder of wood so that the hallow can't spread out.

 

[Sirine]

I did that on above surface. Mid-air to be exect. I have no ideal sunflowers help or not. Somewhere in the middle surface of the map will help. This is due to bugs are critter, and critter are consider a type of monster, they spawn more if other types of monster spawn less. Battle potions and water candle also helps alot.