Details on Rep are hard to find on the Forum. This is what I have - any corrections or updates would be welcome.

1. Daily Arena rank rewards – Automatic Reward for Top 30 (?) 50 (?)(still checking)
2. Arena PVP fights – Daily max 2000
3. Guild contributions (aka investments) – small = 50, decent = 200, grand = 2000
4. Guild Chests – Worth doing “LOOK AHEAD” to see if you get a good flip – predetermined results
5. Guild Tech/Loyalty Card – Up to 30% Rep bonus from Guild contributions, Banish and Daily Arena Awards (Top 50?). This is a ‘l-o-n-g’ term project! Guild tech becomes quite pricey (guild contributions).
6. Guild Warfare – Hold Rep cities (Scorch, Boyleville, Osphiem, Solstafir, Taraniston) 20% Rep Bonus. Stackable to 100% Rep bonus. Still checking what Rep producing events are affected by the GW city bonuses.
7. The Fair – The fastest and least time consuming will be to purchase Reputation at the Fair. This is NOT recommended because gems cost real world money and it can get very expensive very fast.
8. Lab (Cretan Labyrinth) – in flips – predetermined results
9. Attacks in wild/Revenge – Reputation from PvP (payer vs. player) - Another way but very time consuming way to get reputation is by going out into the wild and attacking other players. Keep in mind in order to get reputation this way you have to win the battle. If you lose a battle you started you ’might’ not lose any reputation. Might being the operative word!
10. Weekend Heaven’s Palace – part of level rewards (flips) – predetermined results
11. Banish (aka Cerberus/Baal/World Bosses) – use credits to do the 80% Boost – If you can and it will make a difference use the immediate starts but as it costs gems to do – Be Careful!
12. Ragnarok – use credits to do the 80% Boost – you most likely won’t get as many credits as you use back but we’re talking about how to maximize Reputation.
13. Casino – If it comes up with the “FREE SPIN” great – otherwise save your gems – predetermined results