this is not a guide, just some observations after playing the new hemi.
TURRETS: pros: auto upgrade as you level them + auto attack speed bonus when you plant them + more damage
cons: you can only build 3 instead of 6.
result: even with fewer turrets the ones you make are MUCH more effective than the old ones. before, unless you turtled you would never get all your turrets upgraded and most of the time they were useless as the other team would quickly know where your turret patch was and easily avoid it. now i can plant turret whenever and wherever i want and have their full effect right off the bat, this makes hemi a much more mobile a hero than he previously was. I find my self even using turrets to just kill off weaker jungle creeps.
As for turrets in team battles, honeslty, before did you ever get the chance to make more than 1, maybe 2 in a fight, with the auto upgrade + attack bonus they can contribute a lot more to group fights that happen on the fly.
the only real downside with turrets now is that at end game they are still horribly fragile, with fully upgraded heroes being able to easily take them out in 1 or 2 hits, but they're still much better than before.
ROCKETS: pros: 3 rockets right from the get go, 10 sec cooldown (half of the previous)
cons: less damage
pro/con: target nearest minions as well as heroes.
rockets are now much more spamable. with max CD they are now on a 6 second cooldown, not bad at all. More than makes up for their reduced damage (you figure you're getting twice as many rockets out as before). I'm actually enjoying the new change to them targeting minions, it makes early pushes much more effective, and it is quite easy to kill off several minions and then pop rockets and still hit the enemy hero, you just have to time it right. they are also very good for last hitting creeps or farming jungle creeps. in team battles they're quite good as their damage is still decent and with rylai's you can harass the enemy team nicely.
UPGRADE: now that turrets auto upgrade themselves upgrade is more of just a buff rather than an upgrade in itself. the auto heal + attack speed + slowing attack can be very effective if used correctly, i've turned the tables on a number of heroes who through they could simply turret dive me and get away with it, but grenade stun + slowing turrets gives me plenty of time to either run or finish them off.
Final result: Overall I'm loving the new hemi, the things i go for right off the bat is getting a ton of mana regen and maxing cooldown reduction (not hard at all, get chalice + deathfire and you're set in both respects). from there on i can spam grenades, rockets and turrets to my hearts content. In one case when my whole team had been wiped out in an ambush i managed to hold off the 4 remaining enemy team heroes while they tried to push one of our turrets. by placing my 3 turrets around our main turret and constantly spamming rockets and grenades whenever they got close i was able to hold them back quite well. when they did try one big rush i instantly popped upgrade and as soon as they got hit by the slow they decided to retreat (might be simply because they were not familiar with the new effects).
Hemi is much more mobile and most of all, much more helpful in team battles. he requires a lot less micromanaging than before and isnt completely screwed if ambushed by a twitch or shaco from the bushes. I'll be playing him a lot this weekand to see if he can really be competative in mid ELO now.
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