Super interesting changes coming next patch. I'll summarize them as best I can for those who don't care to dig.
New passive. After not taking direct damage for a while (seemed like 25+ seconds from what I saw), he now takes massively reduced damage and can't be cc'd. After taking damage, the effect lasts a bit longer before going away.
Old W is now appended to his R. New W summons a single voidling for a length of time. The first time a voidling attacks something big or assists in killing a unit, it spawns another voidling, although with the same remaining duration as its creator voidling. 3+ voidlings and they all attack faster. Can get up to at least 6 at rank 1, from what I saw.
E has its duration refreshed by casting Q or R on target, and restores % max mana instead of flat.
R has old W for damage instead of base damage.
Passive now stacks. At 3 stacks it explodes after a bit for a pretty hefty chunk of damage. R now has a Trundle Q style slow tacked onto it. No numbers from what I've seen just yet, but it seems like they're reducing his damage numbers to make him less good at killing dudes alone.
Every 3 Qs he gains bonus damage on it and movespeed for a bit. E is now a charge up like Varus Q, but drains health while charging. R now heals him for a buttload for each champ it pops on.
Passive now spawns random seeds to make plants from around her. W now gives passive plant health instead of CDR. R now gives plants straight damage instead of attack speed.
Q now refunds half mana if it kills a unit, and only he can see the max range split indicator. R now doesn't build up passive stacks, but on champs that recently had passive popped on them it does true damage
Passive is now "can't buy boots, get ms/level instead". W now stops all movement abilities including blinks, but stops at a fixed range (800) or first wall. No stopping people who have already closed the gap. E always heals and always has a short CD and does more damage on poisoned targets.
W no longer cheats its animation. Tibbers does less damage coming down, but persists if Annie dies and does a lot more damage punching shit.
Passive replaced. If he stops for 1.5s he gains huge MS when he moves again. W is no longer permacast. E prioritizes drain targets and bounces more.
Passive is now gain AP from hitting enemy champs with spells and from takedowns. Q gives passive stacks instead of direct AP, same net bonus. All mana costs down. R got a big nerf on damage because Riot sucks at balancing Veigar. Who knew.
Only spawns once, but gives a buff that lasts through death and for 20 minutes and gives you damage reduction and a bonus damage shot every so often while alone.
Turrets keep their damage between targets so juggling aggro early doesn't help as much. Outer turrets give less global gold but more to the nearby champs, inner turrets give less everything. Bonus damage to towers from AP is magic damage. Now have a small amount of Armor/MR and less health, but you can pen the defensive stats. Backdoor protection is flat 2/3 damage reduction.
Overall, really excited for Malz because his ult is no longer embarrassingly bad, or rather his passive enables his ult to be used on occasion. Maybe. Jungle hype is real though.
I can't help but sigh on the Veigar changes. Riot really just needs to either remove him from the game, or accept that large, perfectly reliable, single target nuke is a valid skill when it's 80% of the champion's value. Come back in 5 years and Veigar's R ratio will be down to 20% AP and damage is double reduced by MR.
