If you look at the item's design, it screams "ganking". Regen helps you stay in the field longer. All the other benefits come from ganking. If you get a kill, you get a charge. If you die, it's not so bad when you have charges.
When to Get It
- On #1/2 farm priority heroes (i.e. carry and solo lane) - "Bloodstone Carries/Semi-Carries"
- When you're doing extremely well - it costs a shitload and you need to be getting/involved in a lot of kills for its passive to be most effective
- You're a Ganker or heavily involved in Team fights -- gotta get your charges
- You're Regen dependent
In Short: heroes that need mana regen, will not die often, benefit from flat HP, and are heavily involved in skirmishes/team fights.
When to Give Up
Remember, sometimes it's best to give up on a big item like this. If it's 30 minutes in and you've got boots, Magic Wand, and perseverance, just fuck it. Get something useful (i.e. a utility item like Drum of Endurance or Pipe - which you can break Perseverance apart for). It will help the team more than watching you struggle to complete the rest of your Bloodstone.
Also, if the enemy carry has their BKB before your Bloodstone is done, it may or may not be worth the investment.
Heroes You See This On
- Storm Spirit - dude can use regen. More Ults, more jukes. His spells are all pretty spammable. Also, he's incredibly hard to kill, leading to massive amounts of charges on his stone.
- Semi Carry Leshrac - his spells are spammable, and the better his regen, the longer he can ult. The longer he can ult, the more damage he does in a team fight and it makes it easier to push. NOTE: This is for SEMI-CARRY Leshrac (i.e. not #4/5 support Leshrac - I've made this mistake before, I'm sure others have too)
- Death Prophet - she can spam spells and the added HP helps her take damage while ulting. She can get pretty ballsy for a woman because her ult heals her at the end.
- Necrolyte - at a certain point, he becomes nearly invincible because he can keep spamming his heals. This makes his entire team hard to kill as well. However, Necro really needs some snowball for this to happen.
Heroes it can be situationally good on:
- Zeus - he can spam like a mother fucker, the HP helps him survive. However, it can often be more beneficial to get other items like Aghs, Refresher, etc.
- Enchantress - helps her spam impetus, the extra tankiness makes her more obnoxious due to her Untouchable spell. However, most Enchantress' are played as #4, so it's not really on your itinerary to get a big semi-carry item like this
- Ogre Magi - more spam, more tank. Again, like Enchantress, he's usually not going to have the farm to get a big item like this
- Witch Doctor - justification is basically being a walking Healing Well. However, WD is mostly a support hero at Pro Level.
- Puck - helps with survivability and he's usually a big piece in team fights. Phase Shift helps him survive (i.e. keep charges). He doesn't have the spam to make max use of the regen. Generally seems better to get yourself a Blink Dagger and some utility/initiation items
- Queen of Pain - able to spam to an extent and she has high survivability. A lot of players will opt for more utility or carry items though like Sheep Stick or sometimes a Desolator.
- Semi Carry Lina - again, spammy spells, improves her tankiness, and she also has Fiery Soul, which means the more you spam, the faster you auto attack, giving her that carry potential
Things New Players Generally Overlook
- Bloodstone > Aegis :P
- You keep getting XP in a 1000 radius after death (makes a suicide initiation less sad)
- You gain a massive 1800/1800 vision of the area around your death
Passively, Each Charge:
- +1 Mana Regen/sec (but not HP)
On Death, Each Charge:
- Reduces Gold Lost by 25
- Reduces Respawn Time by 4 Seconds
- Resores 30 HP to allies within 1675 range (in addition to the flat 400 HP) - it's like a Super Mek or Chen Ult
- It's not necessary on anyone, but it's super nice to have
- You can get early Mana Boots, break them apart and have a piece of your Bloodstone ready to go