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From a game last night - can an eldar farseer target a friendly unit while that unit is embarked in a building/vehicle (and therefore 'off the table')?
Same question if the farseer is actually in the building with them.
The only time you cannot target a unit that is "off the board" is when you are deploying in a dawn of war mission as you are actually off the board in this instance. All the other times your unit is on the board you just cant see them.
Does not change if the farseer is with them, they can still be helped.
Army: W/L/D -- Eldar 6/2/2; Orks 1/3/0; BA 1/1/0
The Tale of Two Gamers
This is sadly not the case, GW decided that casting out of a vehicle is fine but casting into a vehicle is prohibited because it's too complicated.
Farseer Fortunes his attendant squad in the back of a Wave Serpent = Fine
Farseer Guides the Fire Dragons next to the Wave Serpent he's in = Fine
Farseer Dooms the Orks in the Trukk ahead = Too complicated, not allowed.
It's in the 5th Ed rules FAQ
"ask not the Eldar a question, for he will give you three answers, all of which are true and terrifying to know"
Children of Isha