Bitcoin reached a new all-time high on May 21, driven by positive momentum and inflows into US-based Bitcoin ETFs.Analysts predict Bitcoin could surge above $200,000 by the end of the year.The formation of a 'golden cross' on Bitcoin's daily chart may lead to further rallies.Altcoins like Ether, XRP, BNB, SOL, DOGE, ADA, SUI, LINK, and AVAX are also showing positive signs.Ether is facing resistance near $2,739 but could rally to $3,000 if this level is breached.XRP is locked in a battle near the $2.35 level, with potential to rally above $2.65 if buyers take control.BNB bulls aim to break above $693, which may lead to a surge towards $745.Solana is eyeing a move above $185 towards $210, while support lies near $164.Dogecoin has bounced off $0.21 and could target $0.26, facing resistance at that level.Cardano may rally to $1.01 if it breaks above $0.86, while support is near $0.69.SUI and Chainlink are also showing positive sentiment, with potential for further gains.Avalanche might climb towards $26.84 and $31.73 if it maintains support above $20.88.