My team to wave 40 was a conjurer, mage, ranger, and a rogue.
Mage was the tanker, and buff reflect can work against you if you are looking to heal. ranger and rogue were my main damagers, and conjurer gave def and made golems.
btw, high level hydras are easy, dont kill the heads so the hydra will only use 2 heads and no regernate heads... and just use range attacks with poison to negate its regernation
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