If a portable altar disappears while you are invoking/praying/whatever, it appears that you get no rewards (no popup showing rewards) but you do get a 1 hour cooldown.
Had this happen in town since I didn't feel like running up to the real altar and people drop portables all the time.
Comments
Yea, I just had this happen to me. Before my invoke ended, the portable altar disappeared and I didn't receive any reward, yet my invoke timer was reset to 1 hour. -_-