What do we have here?
Last letter in order: r, h, e, r
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I think what we have here is
The Four Classical Elements - Air, Earth, Fire and Water
The number of sides of the shape surrounding each image corresponds to the number of letters in the associated element.
The images themselves can join with the element to form a word or phrase as follows:
Plane, corresponding to Airplane.
Mother, corresponding to Mother Earth.
Bon, corresponding to Bonfire (the image is the symbol for Bon Jovi and the tick and cross represent that we want the "Bon" part rather than the "Jovi" part, thanks to the OP for explaining).
Fall, corresponding to Waterfall.
The last letters given in order confirm the answer.