Simply take the bend， the threshold is extremely low， but the later bends present a challenge in design， still demanding considerable skill. The synthesis mechanic certainly has its merits in being straightforward and easy to grasp， yet its drawbacks are equally apparent. Since each tier of car requires two lower-tier vehicles to combine， the quantity needed to synthesise high-tier vehicles later on becomes utterly absurd. Moreover， I‘ve found that high-tier vehicles aren‘t particularly useful for clearing levels； later stages largely come down to your own quick reflexes.