True Tier System Mod 1.7.10
What this mod allows you to do is setup different tiers for yourself. When you start out, you are on tier 0, and are heavily restricted on what you can craft with. When you kill specified mobs, the next tier will unlock, allowing you to craft with that tier’s items, but not with higher tier items.
For example: cobblestone could be restricted until you kill a pig and a cow, but once you do, you can always craft with cobblestone, but not with higher tier items.
Note: You cannot kill a specified mob early to unlock the tier early. You can only unlock the next tier, if you are on tier 0, only tier 1 mobs count, tier 1 only tier 2 mobs count, etc. etc.
Download True Tier System Mod 1.7.10