order of applying die bumps?

:edit: Looks like ‘none of the above’ unless you have access to Powerful Attribute as you cannot bump above 1d12+2 without it.

The Rune bump seems to be included for completeness when used by Threats.

Die Bump: Some spells or Talents may provide you with a Die Bump. Die Bumps can be conceivably applied to any die roll in the game, and unless otherwise noted are capped
at d12. Thus, if you use a Talent that grants a Die Bump to Insight when using a particular skill you simply use the next highest die. If the die is already a d12, you instead gain a +2 bonus to the affected die roll.

Enlarged Hands: Your hands are abnormally large and powerful, making any fine manipulation difficult to say the least. Any time you attack with your bare hands, you gain a Die Bump to your Might (maximum of d12+2), but you suffer a Die Penalty to any Quickness Action
Skill Rolls that depend on using your hands.

Might Rune:
… Unlike a standard Die Bump, if you possess d12 Might, your Might increases to 2d6 instead. …
Special: If this Rune is used in combination with any spell or Talent which grants a Might Die Bump, the effects do stack to a maximum potential of 2d8.

That seems to be the case.

The only other exception I could find was weapon size categories.
Size Categories
The weapons presented in this chapter are of average size. But there are times where the heroes might face larger creatures wielding massive weapons. Weapons gain a Die Bump to their base weapon damage for each category above Average, without increasing the weapon’s Speed. Unlike a heroes die bump which caps at d12+2, weapons which deal 1d12 deal 2d6 instead which each die increasing by one additional size category per die bump. Thus a Huge Scythe, Speed 7, d12 weapon would deal 2d10 (Mi) as a Speed 7 attack.

Die Bumps and Die Penalties
Both Die Bumps and Die Penalties may end up being applied to any die roll. A Die Bump increases any die it is applied to by one step and is capped at d12 unless otherwise noted. If the Die Bump is applied to a die that is already a d12, you gain a +2 bonus to the die roll instead. A Die Penalty reduces the die type by one step to a minimum of d4. If a Die Penalty is applied to a die which is already a d4, you suffer a -2 penalty to the die roll instead.

That makes sense to me. However, my next question is what happens if you only have a d10 base Mi die (since you said you must have d12 to begin with)? Does it end up as d12+2 or as 2d6?