So a lot of people are talking about the new Eldar codex. Two of the standouts are Karandras and this pathfinder sniper. Both of them have their only own little purposes and rules, but they both have infiltrate.
That last part is the problem; a lot of people are already talking about infiltrating any unit with them, not just other infiltrators. The problem is you can’t attach an independent character with infiltrate to a unit without it and infiltrate them.
The infiltrate rules says the following:
Page 38, first paragraph of infiltrate
“Units that contain at least one model with this special rule are deployed last,…..”
Page 38, fifth paragraph of infiltrate
“An Independent character without the Infiltrate special rule cannont join….”
This is usually the point that people stop reading and go like hey “well it doesn't say anything about attaching a character with infiltrate to a unit so that means it should okay, covered by the first paragraph right?” Fortunately it’s not.
In order to clean this up we have to jump to independent character rules:
Page 39, first paragraph under “Joining and leaving a Unit”
“An Independent character can being the game already with a unit, either by being deployed in unit coherency with it or in reserve, by informing your opponent which it has joined.”
What we have here is a classic “cart before the horse” situation. In order for you to infiltrate a UNIT must have one or more the models with his special rule. An Independent character can’t be a part of the UNIT until it deploys, since you can't attach beforehand his infiltrate rule can’t carry over to the UNIT until it’s too late to declare infiltrators. The only place you can attach independent characters to unit not on the table is in reserve and infiltrating is not a form of reserve.
The first part of infiltrate is not trying to suggest, as much as many people want it too, you can attach an independent character to a unit and infiltrate it. This was put in to allow units like Shadowsun with just her drones to work, nothing more.
So short story, only infiltrators or units with character like upgrades can infiltrate. You can’t attach infiltrating Independent Characters to non-infiltrating units and go boo.
….Unless GW plans to Errata/FAQ anything.