Irys seems viable, but her Half-Angel healing trails off to useless eventually, so she seems a lot more RNG reliant than Gura/Ina. Best guess, she needs at least 2 HP boosts per minute to stay ahead of the damage curve. Although I also had terrible luck on Anvils so who knows.
https://files.catbox.moe/uomu7u.PNGStats going into the Yagoo wave
https://files.catbox.moe/17k84r.PNGStats shortly before death