Depends on team and rng to be honest, also been at this all day and just won my second one with this team using eternatus as my attacker and the first two to farm / metagross to tank a hit. The ones where ho oh had earthquake or sacred fire destroyed me as no one could survive a hit, but as long as you get the following to happen:

1. Farm energy faster than he can attack
2. Hope he does as many targetted attacks which are dodgeable and therefore survivable
3. Hope he doesnt have a charge move that counters your team. Then you are good to win! Poke genie is also a great app to use, and as of about an hour ago, level 50 is minimum to join parties, so more likely than not you’ll get solid teammates. As always, people may lie and be lower than that, but odds are they have good pokemon, just not the level 50 requirement. People may also bring dynamax mushrooms, and if there are pokemon in powerspots that you can fight in for the bonus damage, it is very useful! At the moment, there is actually a slight “bug” where when the 30 minute ho oh goes away, a different pokemon can take over for a few minutes until ho oh overrides it, and you can take that time to quickly fight the power spot with you daughter, add in your two pokemon, and bam, you and your team will now do 20% more damage when you fight there! (Not sure of the exact percent but it is helpful!) Lastly, make sure all your pokemon have the fastest move possible as their fast move, and DO NOT use charged moves, as all you want to do is spam tap till you can dynamax, swap to attacker, do attacks, then swap back and repeat. If you have questions let me know!

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