The winners of Eurovision

Eurovision song contest

a rainbow threw up on a cave

A rainbow, with green moved to just above purple (don't get any ideas from that), leads to a cave.

Rainbow out of a fun house, melted leprechaun next to it

A... "Thing" puking a rainbow with strange color

The thing touches the Rainbow.

a happy, smiling, double-syllable cloud

cute cloud wetting itself

Clud with pinks stripes and water dripping out

A lovely candy-striped cloud rains ordinary blue raindrops. What, did you expect it to rain peppermints? That's rather unrealistic.