WoW Upgrades - The Item Upgrader
Upgrades give you an increase in specific statistics. Each upgrade boosts the item level by +3. A random substat is also boosted alongside each upgrade.
The upgraded gear is usually more valuable, unless the item is not required by nature (like FB sorc shields) or a high stat variance (like the eth Titan weapons). Upgrades aren't as useful for the latter because of the requirement to roll an exact version.
Recycle Points
The item upgrader enables players to upgrade their gear to a higher level by providing the appropriate currency to the NPC. Upgrades can be made on any type of armor or weapons. However, the item used to upgrade will be consumed for the duration of time and cannot be used again. Upgrades can be used to create the enchantments.
You can upgrade your gear anytime by visiting the upgrader in any major city. It is recommended that you visit the upgrader once every few weeks, to ensure that your equipment is up to date.
The cost of upgrades will vary based on the current level of the gear being upgraded however, they will always be cheaper than purchasing new gear from other sources. Upgrades such as upgrading a Benthic chest to ilvl385 will cost you 20 recycle points. Buying a similar item will cost you 105.
Valorstones
Upgrades are items which can be used to level up weapons and tools, armor and other accessories. They can be bought by players from item upgrader NPCs in exchange for different currencies, and may also be found in random treasure lists. Once an upgrade has been purchased it can be used on any weapon or tool using an The button will show a preview of an item's next upgrade level, if there are enough materials.
Upgrade costs vary depending on the item slot, and the current item level. For example weapons are more expensive than gloves, bracers, or bracers. Each step costs 15 Flightstones plus a set number of crests. Some upgrades give a discount on the Flightstones. Once an item has been upgraded to a certain degree it is able to be downgraded and sold to the upgrader at a lower price.
Many locations have upgraders for their items, including the main Island and a few outposts. The NPCs offer both an upgrade coupon and the possibility of obtaining the latest recipe. The discount for upgrades increases with the number of items that are being upgraded. It is also possible to be boosted by having players complete specific achievements or complete quests.
Icewind Dale does not have an item upgrader at the beginning, unlike Cromwell from Baldur's gate II. Instead, the NPCs that are available to facilitate upgrades require a variety of means, which is both an improvement but also a drawback.
In Season 3, many new features were added to the upgrade system. After an upgrade has been completed to a specific level for an armor slot, upgrading other items to the same level, will cost less. This is true even if the items are from a different set of equipment.

The discount is available to all accounts. The amount of Harbinger Crests needed to upgrade is cut also, but is only available when certain milestones are reached.
Crests
When upgrading equipment in WoW, players have a few choices. They can choose to use Flightstones, which are a general upgrade currency available to everyone players, or crests that are more specialized and used to upgrade specific levels of items. Crests are a key element of the Dragonflight gear progression system that was introduced in 10.1 and are available in 4 ranks.
The first thing to note is that crests can only be spent on equipment that is of a particular rank, and that each rank has its own requirements for its upgrade path. The simplest and easiest upgrade costs 15 crests. The most complex upgrade requires up to 20 crests, contingent on the type or equipment being upgraded.
Players can earn crests through completing content at the appropriate level. This could be done by doing outdoor activities, or by completing dungeons and raids in all difficulties to get equipment of lower tier or Mythicbosses of raids or dungeons with a heroic difficulty for endgame gear. These crests can be exchanged with an item upgrade r such as Cuzolth or Vaskarn in Valdrakken for the appropriate upgrade steps and pathways.
The new currency system isn't too difficult to use, however it will bring some modifications to the upgrade process. For instance, once an item reaches the highest upgrade level of any rank (Explorer, Adventurer, Veteran, Champion, Hero, or Mythic) it won't need Flightstones to be upgraded. This is to allow players to upgrade their equipment up to the highest possible ilvl on all their characters, instead of relying on seasonal loot.
It's also essential to use crests with care, since they have only one purpose. It is recommended to use your Whelpling-rank crests on the best gear you can locate and save Drake and Wyrm Crests for the next set of upgrades. This is especially relevant for items like rings and trinkets that occupy several slots. The discount on the account will only be applicable if all slots on the character are filled with high-quality gear.