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What are the gold max cards needed? Does it make sense to rent a gold max deck ?

Good question. I try to buy gold max cards for CL (and soon RW) as they are currently in circulation and therefore cheap. I can compete in Gold 1 and my ranking ist most of the time high enough, that I could go to Diamond 3. I tried it last season for the first time and regretted it. Most of my opponents had maxed out cards (really maxed out, not only for Gold ^^) and were wiping the floor with me.
If you want to compete in Gold 1, you should try to have at least two or three splinter with almost all maxed cards for gold and a few neutral monsters. But better players than myself could probably refrain from owning all cards and nonetheless be very good.

Thanks for the tips. Are there any good offers for maxed out gold cards right now?