I came up with this house rule for a player's character, half-orc fighter/cleric, to add some flavor to the class.
Clerics of Norebo can call their deity's favor once a day. All results are valid for the round the call is made.
Roll 2d8.
2. Gambler automatically hits his next attack or makes the next saving throw.
3. One enemy gets a -3 to his next attack or saving throw.
4. Gambler gets a +2 to his next attack or save.
5. One enemy gets a -1 to his next attack or saving throw.
6. Gambler does maximum damage on his next attack.
7. Nothing happens. Lose 50 gp/level.
8-10. Nothing happens. Lose 100 gp/level.
11. Nothing happens. Lose 50 gp/level.
12. One enemy does minimum damage on his next attack.
13. Gambler gets a +1 to his next attack or saving throw.
14. One enemy gets a -2 to his next attack or saving throw.
15. Gambler gets a +3 to his next attack or saving throw.
16. One enemy automatically misses his next attack or saving throw.