You can rank-up in three ways.

1st way

Taking a re-test. You can re-test three weeks after your first test. Re-Test for Slifer Student to Ra Yellow cost 500 EDA Cash and +40 posts.Re-Test for Ra Student to Obelisk Blue 700 EDA Cash + 40 posts.

2nd way

By paying with EDA Cash

From Slifer to Ra - 1200 EDA Cash
From Ra to Obelisk - 2200 EDA Cash

3rd-SPECIAL WAY

Twice per month will be organized a duel against 2 duelists.
An example: Slifer member vs Ra member or Ra member vs Obelisk member.
The winner and the loser will switch their dorms.