Silicon Avatar wrote on May 12, 2010, 14:20: Seems like that kind of makes engineer a one-trick pony.
Agreed, but it could be quite a trick of sentry guns can shoot through portals. Drop a sentry someplace quiet, upgrade to level 3. Shoot a portal on the wall your sentry is facing, then head out. The Engy can open the other end of the portal on a wall and basically make a level 3 sentry magically appear.