In the Lost Empires preview pack, (4GD1b) notes that Death Bolt racks can't be mounted on any unit smaller than size class 4. This seems to be an SFB-ism because AFAIK the size class rules don't appear in FC. So that will need to be addressed when the rules are made ready for more formal publication.
(I dunno how you'll do it. The SFB size class rule unambiguously excludes everything smaller than a true starship, but seems harder to do in FC without explicitly listing which units can or cannot have DB racks.)
Death Bolt rules in Lost Empires e-pack
Moderators: mjwest, Albiegamer
Death Bolt rules in Lost Empires e-pack
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Granted, forgot about them. Also, small and medium ground bases can't use them, either.
Instead of giving a size class restriction or listing units that can use it, I guess the best option is just to say that they can't work in option mounts and can't be used by any ship or unit that does not explicitly state that it uses them.
Therefore, if a ship or unit doesn't explicitly already use death bolts, it can't use them.
Instead of giving a size class restriction or listing units that can use it, I guess the best option is just to say that they can't work in option mounts and can't be used by any ship or unit that does not explicitly state that it uses them.
Therefore, if a ship or unit doesn't explicitly already use death bolts, it can't use them.

Federation Commander Answer Guy