Board Thread:Questions and Answers/@comment-27079808-20180917082740

Lightning → Thunderstorm → Plasma
Because it is a Lightning

Leaf → Thorn → Cacti
Umm.. More Spikier than Thorn???

Fire → Blaze → Lava
Ummmm... Because It's Strong???

Water → Ice → Nitrogen
Cause' Nitrogen is a Cold thing... I Think

Light → Solar → Ultraviolet
Ultraviolet is so strong that is harmful

2 are unknown 