About monster gem selection box at rebuild patch

[myself]

In the case the players’ class tree has changed or skills have been deleted or transferred to a different class, the corresponding monster gem will be deleted and replaced with a ‘Monster Gem Selection Box: Class’.

• Players can select a new monster gem for their new skill set using the ‘Monster Gem Selection Box: Class’.

• ‘Monster Gem Selection Box: Class’ items given to players as replacement will be retrievable from the Market Retrieve tab

so, what is the constrains to get the box?
-should it be attached to equipment first? or you can just put it in storage and it suddenly turn to that box?
-only the mentioned monster gems get the box?

[Umineko]

should it be attached to equipment first?

No, it’s only mentioned that all gems will be removed from their equipment without loss, so you don’t need to fulfill this condition.

or you can just put it in storage and it suddenly turn to that box?

Yes, every monster gem listed in the list will yield you a gem box.

There are also some skills not listed that will result in getting a gem box, i.e. the monster gems of Classes that changed Class tree (Bokor, Thaumaturge, Linker,Squire,Schwarzer Reiter,Corsair,Rogue)

Bokor

• Red Loxodon (Hexing)

• Operor (Effigy)

• Pawnd (Zombify)

• White Gepetto (Mackangdal)

• Brown Hamming (Bwa Kayiman)

• Tombsinker (Samediveve)

• Siaulamb Shaman (Damballa)

  Thaumaturge

• Kepari Shaman (Shrink Body)

• Terraimp Mage (Swell Body)

  Linker

• Coliflower (Physical Link)

• Dandel (Joint Penalty)

• Cyst (Lifeline)

• Velwriggler (Hangmans Knot)

  Squire

• Honeymeli (Arrest)

• Blue Spion (Deadly Combo)

  Schwarzer Reiter

• Green Deadbornscap Archer (Concentrated Fire)

• Socket Archer (Caracole)

  Corsair

• Red Infroblood (Jolly Roger)

• Yellow Moya (Iron Hook)

• Old Hook (Keelhauling)

• Blue Stoulet (Dust Devil)

• Spion (Hexendropper)

• Old Hohen Mage (Quick and Dead)

  Rogue

• Hohen Ritter (Sneakhit)

• Minos Archer (Feint)

• Velaphid (Backstab)

If you combine this list with the list in the FAQ, you have the list of all monster gems that will be exchanged for gem boxes with the Re:build update

[myself]

what a comprehensive answer!
i hope you are right!
btw, at rebuild some monster gem is socketable to any armor part, which is an improvement, hehe

but i checked tosguru just now, skill like arrest and swell body still use the same monster gem after rebuild, so i dont think they will be turned into monster gem selection box

[Umineko]

but i checked tosguru just now, skill like arrest and swell body still use the same monster gem after rebuild, so i dont think they will be turned into monster gem selection box

Since the Class tree of Squire (from Swordsman to Scout) and Thaumaturge (from Wizard to Scout) changed, the gems should be exchanged for gem selection boxes (at least according to the FAQ) even if the gem stays the same and has no changes whatsoever.

It makes sense, since a lot of builds will not be possible anymore after Re:build hits, so you’d have to exchange gems via personal trade or market sale, which is heavily restrictive.