Hello! My name is Raze, a D5 mid/top main who plays on EUNE. I rarely play soloq, but I often play in lower elo to make sure I'm still able to boost efficiently. The prices are the following:
Bronze V--->Bronze IV - 5€
Bronze IV--->Bronze III - 5€
Bronze III--->Bronze II - 5€
Bronze II--->Bronze I - 5€
Bronze I--->Silver V - 5€
Bronze Bundle: 20€

Silver V--->Silver IV - 7€
Silver IV--->Silver III - 7€
Silver III--->Silver II - 7€
Silver II---> Silver I - 7€
Silver I--->Gold V - 7€
Silver Bundle: 30€

Gold V--->Gold IV - 9€
Gold IV--->Gold III - 9€
Gold III--->Gold II - 9€
Gold II--->Gold I - 9€
Gold I--->Platinum V - 11€
Gold Bundle: 40€

Spoiler: Rank proof

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If you are interested, contact me on skype (rajmond.matyas1) or discord (Raze#9861)