I have two questions regarding the Engine's summoning ability: 1) It states a unit is summoned. Is the size of the unit determined by the summoning rules of it's warscroll or by how much reserve points you want to spend? For example, can I spend 360 reserve points and summon 40 Saurus warriors or am I only allowed to spend 100 and get 10? 2) Are the summoned unit free to move in the movement phase?
1) Unfortunately yes and yes. Example : summon warriors : Just 10 and you need to have reserve points. 2) No they cannot. They are under the summoning rules as well. This is why EotG is not used as much, has a good possibility of ending up doing literally nothing in a turn ! Although this is where the Slann comes in with the 4 dice manipulation and so on
Unless there's a FAQ I'm not aware of, this could be debatable. Some units can be summoned in larger numbers if you roll well on the summoning spell (example: basic summon for warriors is a 10 unit, if you roll 11+ you can field 20); so IMO you can call a 20 saurus unit with the EotG if you have enough reserve points. But that would be the limit, no way you can call 40 Sauri.
Yes you are right, I replied in the way of "you cannot for the units that would make sense to be summoned ", my bad @Killer Angel is totally right
Thank you for the fast replies. I have only taken my Engine for a test ride once yet and it was definitely the star of the show. I think I will keep it around with 240 reserve points for a scar vet on carno or another engine.