Splicing, the act of blending two plants or alchemical ingredients. In terms of gardening or herbology this practice would be specific to plants and would require two compatible species of plant to be properly joined. This, however, was not true in either fashion for the act of splicing in alchemy. One could potentially splice an animal and plant together, two or more animals or even two or more plants and they would not even necessarily need to be of the same species. The trouble is that when splicing different species, the difficulty would increase exponentially.
If you tried to splice plants from different species in a normal scenario they may reject each other, they may die off all together or one might kill the other. This would not occur in splicing from an alchemical perspective because much with testing ingredients you would extract the essence of the plants that you wanted to add, and then fuse them into the main plant. This would be a time consuming and arduous process as one essence can reject another if they are opposed but you could still fuse them and stabilize the end product.
The trouble would be when the species were completely opposed such as a desert plant being joined with a form of seaweed from the depths of the ocean. One survived in a dark, wet environment and the other a bright arid one. When joining their essences, they would be highly likely to have a severe rejection. This would mean the failure of the splicing if not handled appropriately but not outright failure from the start.
Fusing essences as a practice would be based on finding similarities between the materials being spliced. This could be something as simple as their color to as abstract as the way the plants interact with a certain element. Finding that one similarity that joined them together was the key between success and failure. The number of points of similarities would determine the ease of splicing the materials but one could succeed even with only one point of similarity.
The next step would be stabilization of the newly spliced material. This could be done in a number of ways but the easiest would be using certain arrays to create a stable environment that would suit the base plant. After creating this environment, one would have to wait for the material to stabilize on its own and begin to grow with the spliced essence. If it would succeed in growing with the additional essence, then the splicing would have succeeded as a whole. However, ensuring that the environment would be just right for the base material would be crucial, any mistake may cause the essence that would be joined to either overtake the base material, destroying it or would lead to total rejection of the splicing. To avoid this the one attempting the splicing would often study the base material and its natural habitat carefully before proceeding with the attempt.
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After the base material fully stabilized, if it was a living substance, as long as it would reproduce one could create a new species. This was often used on plants for alchemy purposes to create unique potions. In some rare, often illegal cases it would be used to create hybrid beasts known as chimeras. This practice was made illegal early on given how rampant and dangerous these chimeras ended up being. As soon as any chimera would be found it was to be killed without hesitation. The spread of such creatures had led to the destruction of kingdoms and the breaking of the usual food chain of the wilds leading to vast destruction.
Now Jien wished to make use of this knowledge to fuse the Serpent Vine with the evolved Mandrake and Creeping Moss. Since he was provided with all three, he felt that it would only benefit him if he could take characteristics of each of the three to make something that would suit what he needed.
The first part of the process would be to figure out what he wanted from each plant and which he would use as the main material. He had originally wanted to just use serpent vine along with some formations for better control and then find a way to use it with his sword, but now he had options and he wanted to give them a try to both acheive his goal and dip his toes into the three professions he was advised to train in.
Serpent Vine was known for acting like a constricting serpent when around living beings. It would wrap around them and constrict them until they would die. On top of this behavior, they had their poison thorns. Both of these were things that Jien wanted. He felt that if used correctly the aggressive nature of the vine would be positive for battle as long as it could be controlled.
Creeping Moss was attracted to living beings more so than Serpent Vine was. It would then swarm whatever it found, expand to cover it and suffocate it before using it as fertilizer. This made it dangerous to enemies both big and small alike. Jien wondered if he could somehow use the expanding aspect of this plant to make a weapon that would grow in size if needed, or perhaps some way for the weapon itself to devour prey. This would then alleviate Jien from being used as an energy source. The only trouble would be that he would then have to feed the weapon like he would an animal.
Lastly was the evolved Magic Mandrake. The only thing from this plant that Jien would want is that tough it was 'intelligent' in that its behavior was closer to that of an animal than a plant, its behavior was more docile. These plants though rare were sought after because if properly cared for one could easily grow more. The issue was that the survivability of new sprouts was abysmal. However, the mild-mannered aspect of this particular plant made it more than perfect for Jien's project.
If he could take aspects of the two other plants and then use the mild nature of the mandrake to have better control of the resulting plant, he would be one step closer to his goal without adding additional steps to the next parts of the project.