re: Just recently started Bloodborne.

Summoning raises the HP of the boss.

If you summon and they get killed, it's next to impossible to beat some of the bosses due to the extra (i think its 1/3) HP they get from the summon.

My rule of thumb first playing it, fight the boss around 10 times before summoning. You really start to learn the patterns after mulltiple attempts, and should get better every time. Make sure to watch the bosses patterns, windups, etc. Some are better dodged straight at them, others to the side, backwards, etc.

Also, if you are having trouble with one in a certain area, go around farming echoes and vials and level up around 5 or so levels (mainly to the stat that scales with your weapon and vitality for HP) and try again. Also, note that sometimes rolling to dodge is better (non locked on O button) than quick stepping when locked on.

Part of the brilliance of this game is the bleak nature of dying and dying over and over to a boss, then finally taking him down solo, it's an addicting rush that 3 years later still gives me that "wow" factor of emotions.

I started a new playthrough going bloodtinge and skill (just got the simon's bowblade early, and going after th chikage now) and it's like a whole new game. My first playthough I did STR, then quality Arcane with Holy Moonlight Sword which was awesome.

So much replay value.

Also a word of advice you may not know. Transform attacks hit harder than regular. Do an attack combo (R1, R1, etc) then on the third swing press L1 to transform the weapon, it's a unique attack that also gets the weapon to the transformed mode, and hits harder than just spamming r1. (it also opens up beasthood but thats advanced for now) Get good at using transform combos back and forth. (R1, L1, R1, R1, L1, etc) It will open up the game immensely and change how you approach fights. Really you can do them however you want, just start adding L1 to your combos and experimenting with it.