Habroxia 2 (HP)

You can do this on any level but it's recommended you do it on Level 1. Try and avoid getting hit until you reach one of the final bosses. Get their health down so they only need 1-2 hits left, then just run into their attacks until you have less than 25 HP. Thor as an example will do 20 damage to you each time he hits you so you can do the math from that to see how much you need to get hit to get under 25. Once you're low enough, finish off the boss and when you get to the level complete screen, the trophy will unlock.