There can be up to 3 on each official server, I have seen 2 on the same heatwave. Tame with 2 mate boosted fire wyverns 600mleee then pump Stam, hop between wyverns when you run out of stamina. Trap In a 5 high 1x1 with fence foundations and doorframes, not double door, use pillars to make a platform with ceilings on the 2nd doorframe high, it took me 40 seconds to tame a 40 and about a minute to tame a 50 on 4x taming

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