A lot of players seem to struggle deciding which bonuses in the Obelisk of Power they should prioritise. Whilst I am normally hesitant to be so prescriptive in this case I will give a list of desirable bonuses and a suggested order of learning. I won't be listing any of the bonuses required along the way, I'm sure you can manage that on your own.
Wait... you do know that you only need to train each prerequisite to level 8 or 10 before the next bonus becomes available right? Right.
1) Discovery Speed 20/20
2) 1st Additional Raid Attempt 10/10
3) Discovery Speed II 20/20
4) 2nd Additional Raid Attempt 10/10
5) 3rd Additional Raid Attempt 10/10
6) Combat Experience 20/40
7) Food Consumption 80/80
8) Darkening Cost 50/50
9) Combat Experience 40/40
These are your core bonuses. If you are someone who uses settlements often you may at this point want to pick up Maximum Settlements 30/30, for everyone else I would start looking at Training Times.
When selecting units to apply runes to, consider that all the bonuses reach the same final percentage (12%) but there are a varying number of levels, 40 or 50, so that means the 50 level units require a greater investment of runes and time for the same result as a 40 level training time bonus, but other units have many more units before it that you will be required to level up partially before you can level the one you want.
With that said my suggested Training Speed units are:
Griffins
Golems OR Demons
Knights OR Great Lords
Pikemen OR Paladins
Nomads
Archers
Warlocks
Wyverns
Huntresses
Great Lords OR Knights
Paladins OR Pikemen
Undead Dragons
Silent Ones
Demons OR Golems
By which point you may want to start looking to improve the movement speed of certain units, but that's for a later date.
