The way vitality is calculated makes the -50% from glass cannon differ in actual vitality decrease by a lot.
Normal mode gives a +15% vitality bonus meaning that a character without Lone Wolf, Picture of Health or Glass Cannon has 115% vitality. Taking Glass Cannon reduces vitality by 50% through addition.
115+(-50)=65%. 65 is 56,5% of 115 resulting in a 43,5% reduction of vitality.
Hard mode gives a -25% vitality reduction meaning that a character without Lone Wolf, Picture of Health or Glass Cannon has 75% vitality. Taking Glass Cannon reduces vitality by 50% through addition.
75+(-50)=25%. 25 is 33,33...% of 75 resulting in a 66,66...% reduction of vitality.
A normal mode glass cannon character (65%) has almost as much health as a hard mode character without it (75%).
Your other hero has Lone Wolf which means 75+(-50)+70=95%. That gives him 95/25 = 3,8 times a much health. Verifying this by Dividing 200 by 3,8 gives us the correct amount of vitality. 200/3,8 = 52,6.
