edit: Update through 2.5...
S tier (game-changers):
Byregot's Blessing (CRP50, 24CP)- Converts Inner Quiet stacks into quality gains and removes Inner Quiet (IQ control bonuses remain). This skill allows you to finish HQ synths at approximately 50% of the quality bar (with Great Strides). It is also a key component to "guaranteed HQ" scripted synths.
Hasty Touch (CUL15)- In combination with Steady Hand (preferably SHII), Hasty Touch lets you grind out quality without draining your CP, as it's the only quality-add ability with no CP cost (only durability). It's particularly useful for synths that are still challenging, or if you have a low CP gear build.
Tricks of the Trade (ALC15)- TotT allows you to convert Good condition into 20CP, which (particularly when used with Hasty Touch) lets you string out synths for super long grinds. Near the beginning of a synth (when your Inner Quiet hasn't yet gotten enough stacks to give you large quality gains), it's amazing.
A tier (extremely useful):
Careful Synthesis I/II (WVR15/50)- Both of these progress-gain skills are essential for their 100% success rate, which allows you to plan for progress completion without worrying about bad luck or reserve CP. You should definitely have at least CS.
Comfort Zone (ALC50, 66CP)- 66CP cost, 80CP return (over 10 turns), 14CP net. The extra CP is obviously useful, but CZ also serves an important purpose in putting some space in your CP bar (in the early part of a synth) so that you can take advantage of any TotT procs.
Ingenuity I/II (BSM15/50, 24/32CP)- These skills are primarily for increasing the progress and quality gains on */**/*** recipes (by "slightly lowering" or "lowering" the recipe level, respectively), and they work very well for that.
Manipulation (GSM15, 88CP)- Restores 10 durability per turn for 3 turns; this is calculated AFTER durability actions, so if you use this at 10 durability and perform a durability consuming action next, you will botch the synth (because you hit 0 before you get 10 back).This is the second-most CP efficient durability restorer (behind Master's Mend II) and unlike MMII, is feasible for 40 durability recipes. It's also very useful in planning ahead; at 30/40 durability, you can use Manipulation -> SHII and use all five turns of SHII, which you cannot do with the lump sum durability restorers.
Steady Hand II (CUL37, 25CP)- Success rate+30%. Steady Hand I (+20%) is good, but Steady Hand II turns Basic Touch into a guaranteed action (essential for guaranteed HQ scripts) and makes Hasty Touch much more reliable.
Waste Not I (LTW15, 56CP)- 50% durability reduction for next 4 turns. Strictly speaking, it's a better CP/durability ratio than Manipulation; since the game treats 5 durability the same as 10 durability at the end of a synth, you can actually use a non-durability action during one of the 4 turns and still get the same effective durability reduction.
Piece By Piece (ARM50, 15CP)- Increases your progress by 1/3rd of what's remaining (90% success rate). The "remaining" part is key, as it's like the old adage of getting from point A to point B by moving halfway each step; your gains get smaller and smaller. But PBP is a very useful tool for some of the new *** recipes with HUGE progress requirements.
Reclaim (CUL50, 55CP)- Grants 90% chance of ingredient recovery on a botched (not canceled!) synth. If you've had a horrible run of luck and it's HQ-or-bust, you can use Reclaim as a reset button. Be advised that Rumination will give 54CP for 9 IQ stacks. On some of the harder synths that are necessarily luck-dependent, this skill is very useful.
B tier (situational accessories):
Innovation (GSM50, 18CP)- Control+50% for the next three steps. In most situations where you want the extra control, Ingenuity is probably going to do more for you than Innovation will. You can stack this with Great Strides for an even more powerful Byregot's, though.
Rumination (CRP15)- Converts Inner Quiet stacks into CP and removes Inner Quiet (IQ control bonuses remain). The CP return on this skill was lowered considerably from beta (it now gives 59CP for 10 IQ stacks). If you don't have Byregot's, you can use Rumination if you've completed your quality phase and you need CP to finish your progress. If you do have Byregot's, the only real purpose for Rumination is for Reclaim.
Brand of [element] (various37, 15CP)- These are useful for Vintage gear recipes and some housing items, which have elemental instability that greatly reduces standard progress gains.
Waste Not II (LTW50, 98CP) - In order for this skill to be more CP/durability efficient than Manipulation, you have to use at least 7 durability-consuming actions in 8 consecutive turns.
C tier (gimmicks):
Flawless Synthesis (GSM37, 15CP) - Gain 40 progress. It has some use at very low levels, but 15 CP for a progress ability with only 90% success rate is not a good deal when CS/CSII are 100% and cost 0 CP.
Rapid Synthesis (ARM15) - Gain 250% progress, 50% success rate. If you don't mind high RNG factor in your synths, you may have a use for this.
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Some resources:
- list of which AF is crafted by which class
- still-mostly-accurate crafting reference guide from beta4
- spreadsheet with materia caps and optimal melds for all slots (except militia offhand, which cannot be fully capped in 5 melds)
- materia melding guide with less T4 materia (but more forbidden melds)
- list of items needed to turn in for crafting class quests
Progress formula:
Progress = round ( (1 + 0.05 * recipe level difference) * (0.21 * Craftsmanship + 1.6) )
- For every level a recipe is above you, up to 5 above, you take a 10% penalty to progress.
- For every level a recipe is below you, up to 5 below, you gain a 5% bonus to progress.
- For every addition level greater than 5 level below you, you gain another 2-2.5% (needs refinement) bonus to progress, until 15 levels below you.
- After 15 levels, it continues to gradually increase until around 55% bonus
Quality formula:
Quality = round ( (1 - 0.05 * recipe level difference) * (0.36 * Control + 34) )
Level difference is only a quality penalty for recipes above your level, never a bonus for recipes below your level.
1-step 100% HQ macro for 1* 40dura mats @ 324CRF 395CTL 338CP:
Spoiler: show
100% HQ script for 80dura 2* recipes @ 357CRF 344CTL 341CP:
Spoiler: show
HQ 3* Macro set:
Spoiler: show
Guide for crafting 4* master book items:
Spoiler: show
4* craft simulation @ 452CRF 409CTL 398CP (1 TotT proc required)