Not really thieverish, but just some crazy idea. 
Basically, theres a new button added to the controls that says 'mix/combine'.
Once you hit the mix button you have to select an inventory item and rightclick, then that item gets added to the mix.
As soon as you have a viable mix with the right ingredients, a new 'mixed' item will automattically be created... most items need only two items, but there are some that need more.
As soon as you press the mix button again, or leftclick, you stop mixing and return to normal mode.
Mixed/combined items cannot be unmixed/uncombined.
Aslo, I have some new items solely for mixing that could bought by thieves or guards, further info below.
Possible mixes/combinations:
Health + Health
Greater Health Potion
+60 health (+10 health bonus).
Speed + Speed
Greater Speed Potion
25 seconds of speed (+5 second bonus)
Invis + Invis
Greater Invisibility potion
25 seconds of invisibility (+5 second bonus)
Catfall + Breathing
Silence potion: colour Black
20 seconds of silence
- No screams when you take damage
- No footstep/fall sounds (you do take fall damage though)
- No potion gul'p sounds
Invis + Speed + Catfall
Ghost potion: colour White
Ghost effect for 10 seconds.
- No fall damage
- No footstep/fall noise
- 50% speed boost
- Cannot take damage (ethereal effect)
Flare + Flare + Flare
Dynamite
A flare that doesn't emit light, except for a small flash when it explodes after 3 seconds, same damage as a mine but a slightly larger radius.
Don't mistake them for flares, or they'll go boom in your own hands.
Repair Tools + lockpicks + lockpicks
Advanced tool kit
Repairs everything twice as fast and can be used on lockpicked (not unlocked with key!) objects to relock them again.
Chicken + Cucumber + Carrot + Cheese
Food Dish
Full heal! (+125 health!)
Deer leg + Bread + Cucumber + Cheese
Food Dish
Full heal! (+125 health!)
Cookie + Cookie + Cookie + Cookie + Cookie
Health potion
Just as a quirk mix, hehe
New Mix item: Mushroom!
Item that can be used in many mixes which can be bought for 20 loot, but only by thieves.
Item is dropped when the owner dies.
When this item is used (not in a mix) it'll give the user +5 health (about two drops?).
Health + Mushroom
Unhealthy Potion
Woe to the guard or thief that mistakes this potion for a true potion and uses it.
It looks exactly like a health potion (save for the name) but instead of adding 25 health, it substracts it.
User takes 25 damage.
Speed + Mushroom
Spiked Potion
It looks exactly like a speed potion (save for the name) but instead of giving the player 10 seconds of double speed, this potion paralyses the user for 10 seconds.
User is paralysed for 10 seconds.
Catfall + Mushroom
Crackfall Potion
It looks exactly like a catfall potion (save for the name) but instead of giving the player 20 seconds of catfall, this potion gives the user 20 seconds of crack effect.
User is 'cracked' for 20 seconds.
Breathing + mushroom
Toxic potion: Orange
Potion behaves like a flashbomb, but when it is thrown it will create the crack gas effect wherever it lands.
This potion can not be dropped, whenever it is dropped it will produce the crack effect instantly... it will be dropped when the person who carries it dies though, providing for a malicious afterdeath revenge effect.
If you like this idea, post your own mix idea's

Basically, theres a new button added to the controls that says 'mix/combine'.
Once you hit the mix button you have to select an inventory item and rightclick, then that item gets added to the mix.
As soon as you have a viable mix with the right ingredients, a new 'mixed' item will automattically be created... most items need only two items, but there are some that need more.

As soon as you press the mix button again, or leftclick, you stop mixing and return to normal mode.
Mixed/combined items cannot be unmixed/uncombined.
Aslo, I have some new items solely for mixing that could bought by thieves or guards, further info below.
Possible mixes/combinations:
Health + Health
Greater Health Potion
+60 health (+10 health bonus).
Speed + Speed
Greater Speed Potion
25 seconds of speed (+5 second bonus)
Invis + Invis
Greater Invisibility potion
25 seconds of invisibility (+5 second bonus)
Catfall + Breathing
Silence potion: colour Black
20 seconds of silence
- No screams when you take damage
- No footstep/fall sounds (you do take fall damage though)
- No potion gul'p sounds
Invis + Speed + Catfall
Ghost potion: colour White
Ghost effect for 10 seconds.
- No fall damage
- No footstep/fall noise
- 50% speed boost
- Cannot take damage (ethereal effect)
Flare + Flare + Flare
Dynamite
A flare that doesn't emit light, except for a small flash when it explodes after 3 seconds, same damage as a mine but a slightly larger radius.
Don't mistake them for flares, or they'll go boom in your own hands.

Repair Tools + lockpicks + lockpicks
Advanced tool kit
Repairs everything twice as fast and can be used on lockpicked (not unlocked with key!) objects to relock them again.
Chicken + Cucumber + Carrot + Cheese
Food Dish
Full heal! (+125 health!)
Deer leg + Bread + Cucumber + Cheese
Food Dish
Full heal! (+125 health!)
Cookie + Cookie + Cookie + Cookie + Cookie
Health potion
Just as a quirk mix, hehe

New Mix item: Mushroom!
Item that can be used in many mixes which can be bought for 20 loot, but only by thieves.
Item is dropped when the owner dies.
When this item is used (not in a mix) it'll give the user +5 health (about two drops?).
Health + Mushroom
Unhealthy Potion
Woe to the guard or thief that mistakes this potion for a true potion and uses it.
It looks exactly like a health potion (save for the name) but instead of adding 25 health, it substracts it.
User takes 25 damage.
Speed + Mushroom
Spiked Potion
It looks exactly like a speed potion (save for the name) but instead of giving the player 10 seconds of double speed, this potion paralyses the user for 10 seconds.
User is paralysed for 10 seconds.
Catfall + Mushroom
Crackfall Potion
It looks exactly like a catfall potion (save for the name) but instead of giving the player 20 seconds of catfall, this potion gives the user 20 seconds of crack effect.
User is 'cracked' for 20 seconds.
Breathing + mushroom
Toxic potion: Orange
Potion behaves like a flashbomb, but when it is thrown it will create the crack gas effect wherever it lands.
This potion can not be dropped, whenever it is dropped it will produce the crack effect instantly... it will be dropped when the person who carries it dies though, providing for a malicious afterdeath revenge effect.
If you like this idea, post your own mix idea's

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