D-Mod

D-Mod is a mod that backports some features from later versions of Minecraft to 1.7.10. You could consider it an add-on to Et Futurum Requiem (though it's not a hard dependency).

Currently implemented:

Foxes
Bundles

Foxes

Foxes have some (optional) extra features implemented. Untamed, they behave the same as they do in new vanilla versions. But as they defeat enemies, they gain EXP and unlock various new abilities and AI improvements.

The major ones are getting healed when fed food, following the owner after being fed a sweet berry, and possessing Looting I intrinsically (does not stack with swords that have Looting). Foxes pass down their EXP to their children.

More info in the wiki.

Dependencies

Item icons in bundle tooltips will only be drawn if NEI is installed (I recommend the GTNH fork).
Et Futurum Requiem is highly recommended as it backports sweet berries (useful for foxes) and rabbits (useful for bundles).

Incompatibilities

Hodgepodge: set preventPickupLoot=false or else foxes won't be able to pick up items
Various coremods will crash during startup due to an incompatibility with Mixin. For example, Backlytra crashes if D-Mod's lootingFoxFix is enabled. This is fixed by Mixingasm.