In League of Angels, The Forge is a system that allows players to improve the stats of their character and heroes. 

The first method of upgrade is through enhancement. This increases the stats already existent on the equipment item. Enhancements cost progressively more each time they are applied to the same item.

There is also an “Enhance All” function that lets the player set the amount of times they want the item to be enhanced at once; this ensures the desired amount of enhancements and saves quite a bit of time.

  

  

The second tab in the Forge menu is socket. 

Gems may be put into equipment to increase their effectiveness in battle. Socketing allows for stat customization; there are currently eleven different types of gems in the game, each with their own stat. 
It is up to the player to decide whether it should be used for reinforcing a weakness or making a strength even more potent.
There are, however, limitations; only one of each type of gem may be socketed in the same item, regardless of level.
Socketing Rods, acquired from Gemology and various shops, may be consumed to open new sockets on equipment. By increasing the sockets, the item’s stat portfolio is broadened when it becomes fully gemmed.
Gems can also be reused. When swapping out a gem for a better one, unsocketing the old gem does not destroy it. It can then be used on a different piece of equipment.

  

  

The Synth tab in the Forge menu allows players to craft items.

Equipment, gems, and other items such as Holy Crystals may be crafted here. The materials required will be displayed on the right. 
Everything other than gems may be crafted with a 100% success rate. Gem synth, on the other hand, has a 25% chance to fail. To prevent loss of gems, players may consume Synth Scrolls, acquired from various in-game shops.

  

  

The fourth and final tab of the Forge menu is Exchange.

Gems and weapons can be swapped here for a small gold cost.
Gems can be exchanged for any other type of gem at the same level. This is also the case for weapons. Level 40 weapons can only be exchanged for other level 40 weapons; level 60 weapons can only be exchanged for other level 60 weapons.