The old man gave me two new tasks today...one to hunt 100 animals, the other to use 6 blessings. The third space is still blank, but at least some timed challenges have reappeared. I generally complete most of the challenges on donating troops and hunting. I hardly ever complete the timed challenges on battles. The rewards in terms of gems are pretty minimal, but it's not a bad thing to be encouraged to hunt a bit more and donate to your alliance. On the long term challenges (just underneath the old man) I have only completed 32 out of 57 challenges.