There are 8 basic types of Stimulants in the game.
You can improve the potency of your Stimulants by combining together two Stimulants of the same level and type in order to get one new Stimulant of a higher level. By repeating this process, you can upgrade Stimulants up to a maximum Level of 12. The higher the level of the Stimulant, the better bonus it will grant to your forces once activated.

To combine Stimulants, go to your Medical Laboratory, open the "Operation Room" tab and choose the Stimulants you wish to combine. Click "Select" and they will appear in the "Combine Stimulants" section of the window. You will also be able to see the bonus you receive once the Stimulants are combined together. Click "Combine" to produce the higher level Stimulant. Once combined, the Stimulant will be immediately sent to the Cold Storage.
ATTENTION: To upgrade the Stimulants of higher levels you need to upgrade the Medical Laboratory.

You can receive Stimulants by:
- Purchasing them at the Black Market within the "Misc." tab;
- Participating in Global Tournaments;
- Challenging other Combines;
- Attacking or defending Zheng-Shi Locations;
- Other game interactions.

All Stimulant Boxes acquired will be sent to your Cold Storage within the Medical Laboratory, where you may open them and extract the Stimulants.

To use and store Stimulants, you must first build the Medical Laboratory. All Stimulants gained in the game are stored in the Cold Storage at your Medical Laboratory. To view a Stimulant's attributes, simply place your cursor over it. To apply any Stimulant and benefit from its bonuses, simply place it into any open Activation Slot on the Activation Board. BE AWARE: You must use a Centrifuge to open additional Activation Stots. Stimulants are permanent bonuses, and will not disappear from slots unless you decide to remove them.

Once applied, you can only safely remove Stimulants and return them to your Cold Storage with the help of a special tool – the Injector. This tool can be purchased from the Black Market. Removing the Stimulants without the help of an Injector will result in the Stimulant being permanently destroyed!

Keep in mind that there are two types of Injectors:
Jet Injectors can safely remove Stimulants Level 5-8
Nano Injectors can safely remove Stimulants Level 5-12

WARNING: Each Injector is only "single-use" and may be used to extract only ONE Stimulant.