CE bomb 101

Step 1: Summon on the FP gacha until you're out of FP or out of room

Step 2: Take one of the low-star CE (Tenacity, Meditation, Technique, Preemption, Destruction, Flash, Opportunity, Fruitful, Concentration, Divine Oracle- you can decide whether to do it with the 3* CEs as well or to burn those for Mana Prisms) and combine it with every copy of itself. So, if you have 8 Tenacity, combine them all into one MLB one that would probably be at level 6 or something.

Step 3: Repeat Step 2 with every other low-star CE. Now you'd have 10 (assuming you had all of them) MLB CEs, all lower level.

Step 4: Choose one of those (say Tenacity) and then add all the others to it and Enhance. It'll still be low level (maybe 20?), but you've now cleared up space to go through the entire process again.

Step 5: Summon more on the FP gacha, repeat all the other steps, but when you're done don't add them to the one from Step 4. Choose a new MLB one that is a lower level, and add the one from Step 4 to that. Keep on going.

Hope that helps, but really it seems like something where watching a video would be better than reading how to do it.

Fill a lvl 1 1* CE with as much exp as possible. Pick a different lvl 1 1* CE, fill with as much exp as possible plus the previously filled 1*. Make sure you have enough to level break to hold the accumulated exp. Repeat over and over until the bomb is nearly maxed and feed to the mlb ce of your choice.

Order matters when selecting the exp to add. First select the exp fodder, then select the bomb in work, then select the cards to level break. Otherwise you won't be able to add much each time.

Always adding new exp to a lvl 1 1* keeps the qp cost to 60 per card (even when it is a bomb that can take it from lvl 1 to lvl 40, otherwise the cost climbs rather exponentially with level and you burn millions of qp leveling the ce.

get a 2* craft essence, mlb it and dump in enough 1*s to make 18k xp. get 5 like them and dump them into a 3* to get a level 18 CE, then get 20 of those lv18 3*CEs and dump them into a mlb 1*CE for a level 50 bomb worth 2m xp

The one that to me shows you the least-QP cost way is:

https://www.reddit.com/r/grandorder/comments/8cpief/craft_essence_ce_bombs_for_dummies_rev_2_electric/

but it took me a while to understand it.

The thrust of it is that with the exception of the last step of making a 1M XP CE bomb, you only ever level up a blank 1*. And you only feed 18k plus the extra copy of itself at a time, so you can take advantage of any super/great successes without capping out.

So you start with a bare 1*, feed it 18k XP (e.g., 18x1*, 6x2*, or 3x3*, or any mixed combination you want) plus one copy of itself. This makes a 19k (or more if you get a super/great success).

Next you take a another bare 1* identical to the one you started with last time, feed it another 18k, plus the 1* you built in the previous step. This makes a 38k card. Repeat the process again, which will make a 57k, repeat again for a 76k, and again for a 95k. This requires, if I counted correctly, 6 copies of a single 1*, since you need to be able to LB each iteration with the copy from the previous.

If you want to then make a single 1M XP bomb, you can LB a 1* 3x (apparently, no need to MLB it), feed it 9 of the 95k bombs you make using the above proceedure plus a smaller one (38k or 57k). This is the only step where you have to start with a CE leveled above 0.

BTW, you can only crit (i.e., super/great success) with the intrinsic value of a card, and not accumulated XP. In other words, If you feed the "big bomb" 1M XP CE from the above, the only multiplicative XP you can get is from the 1* card itself, and not the rest (because it already had the chance to crit, whether it did so or not). While this might sound detrimental, at least you don't have to worry about "wasting" an extra 1M XP if it worked that way and you capped out on whatever you fed it to.