And this is my answer 
Though I must say that specialization tree is not finished… but I’m close to finish it 
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First of all: I think current skill’s functionality is very similar to “Elemental Nova” with Frost specialization. And as far Elemental / Frost Nova’s functionality is quite good and fitting its nature I’d suggest to slightly change Shatter Strike itself (I’ll try to keep animation similar to existing one).
Shatter Strike: Two slow waves of snow deal damage to enemies around and clash in front of the mage. Enemies caught by the clash get additional damage and may freeze.
Visuals: It is similar to existing one. Though …
- two waves appear instead of one.
- waves initially appear behind the character rather than in front of him.
- area of effect is not centered on the mage. It’s center is shifted forward now, and so 30% of diameter is behind the mage and 70% - in front of him.
- waves move around the mage and clash in front of him (like scissors). Additional clash effect required.
Functionallity:
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Shatter Strike is a melee attack which depends on character’s melee attack speed, but it slowed by 60% comparing to a basic attack.
ShSt Aspd = Weapon Aspd * (1 + Aspd bonuses) / 1.6 -
waves’ movement speed is depend on character’s attack speed. They appear when attack starts and clash when it ends. So if weapon attack speed = 1.2 attacks / sec (with bonuses), than …
ShSt Aspd = 1.2 / 1.6 = 0.75
… which means …
Clash delay = Attack interval = 1 / 0.75 ~ 1.33 seconds.
This delay should compensate skill’s great area size (comparing to Frost Nova). -
Clash area’s angle (and area of freeze effect) is only 30 degrees which is obvious and significant difference with Frost Nova.
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Culling is no longer a basic effect of the skill.
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Wave damage can be taken once per 0.6 sec. And yet it’s impossible to take damage from both waves simultaneously (fox example, standing in the middle of the wave clash), but it is possible to get wave damage several times …
- relocating to a front of a wave after being damaged by any of them.
- moving inside the wave.
- having large hitbox enough to stand inside the waves more than 0.6 sec.
- standing close to the mage increases the chance to get additional damage.
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Wave damage interval is individual for each enemy and each use of Shatter Strike. So there must not be any problem with high attack speed and small attack intervals.
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Normally wave’s speed is enough to NOT deal multiple damage to enemies which have small / normal hitboxes and stand still. But in other cases this mechanics allows to make waves working as … waves
. -
If mage is interrupted waves won’t work anymore (damage or any other effects), though visually they won’t disappear immediately. Waves become “weaker” and continue to move for 0.4 seconds with 40% reduced speed.
Specialization nodes :
Crushing waves: [5 levels]
Increases skill’s critical strike chance by 20% per node level and grants it 2% culling strike per node level.
Frost maims: [4 levels, requires Crushing waves 1 or Bury the weak 1]
Skill’s critical hits have 50% chance per node level to cause Frostbite effect on the enemy. I’ve noticed that @Trasochi mentioned Frostbite’s ability to stack, so I’m using it (11.05.2019, discord chat: ask the devs).
Bury the weak: [1 level, requires Frost maims 2 or Wave hammering 2]
Skill’s base critical chance is increased by 4% and culling threshold is increased by 4%. Unlike most culling effects this bonus is additive. So if character has 14% culling strike from buff, 10% culling strike from passives, “Bury the weak” bonus is added to 14% resulting 18% culling strike.
Wave hammering: [6 levels, requires Bury the weak or Cold mind 2]
Increases skill’s critical multiplier and freeze chance by 17% per node level.
Cold mind: [4 levels, requires Wave hammering 2 or Heart freeze 1]
Grants a buff which increases skill’s critical chance and multiplier by 70%. Buff disappears after 0.5 seconds when critical strike is dealt and reappears 10 seconds after that. Each next node level decreases reappear delay by 2 seconds. So the minimum delay is 4 seconds. I also have doubts about “Cold mind” name as it fits better to a Rogue class. “Shatterer’s time / moment” may be? .
Heart freeze: [1 level, requires Cold mind 2 or Permafrost 2]
Increases base critical multiplier by 20% (so it becomes 220%). Skill’s freeze chance is also increased by critical multiplier / 3 when critical strike is dealt. This freeze chance bonus is additive, not multiplicative. For example, having +150% freeze chance and 450% critical multiplier will result (1 + 1.5 + 4.5 / 3 ) * 100% = 400% freeze chance.
Jaws of Winter: [4 levels]
Increases attack speed penalty by additional 5% per node level, but also increases area of effect by 5% per node level and skill’s damage by 10% per node level. With this node speed penalty increases to 80%, but the damage bonus is multiplicative so it remains effective at any game stage.
Freezing tides: [5 levels, requires Jaws of Winter 1 or Leviathan’s grasp 1]
Waves gain 6 freeze rate per node level and clash freeze rate increases by 3 per node level. Wave bonus may be very important as the skill has no freeze rate on waves by default. Clash bonus may seem weak but it is added to a base value so it may become really useful when maxing freeze chance.
Leviathan’s grasp: [1 level, requires Freezing tides 2 or Heavy pushes 2]
Increases clash area angle by 30 degrees. Enemies caught by waves have 30% chance to be pushed in the direction of their movement. Distance of push is limited, so, for example, if enemy caught at the wave start it can’t be moved over entire circle. Also distance of push depends on distance to the caster - closer enemies are pushed weaker, so it’s nearly impossible to deal additional wave damage after push. Also enemy can’t be pushed when it’s inside of clash area or if the distance between it and the mage is less that 30% of radius.
Heavy pushes: [5 levels, requires Leviathan’s grasp 1 or Permafrost 2]
Enemies caught by wave clash have 15% chance (+ 3% per node level) to be knocked back. Knocked back and pushed enemies (by Leviathan’s grasp) takes increased damage from waves and clash - by 20% per node level. Enemies cannot be pushed and knocked back withing the same skill usage and so can’t take twice increased damage. Enemies immune to such control take increased damage anyway.
Ice Grinder: [1 level, requires Heavy pushes 4]
Wave clash pulls enemies to the mage instead of knocking them back. Also enemies take up to 30% additional damage from waves and clash depending on their proximity to the mage. Additional damage equals 0% on the border of skill’s AoE. But when the distance to an enemy reduces to 20% of radius - damage bonus is maximized. Enemies can’t be pulled when that distance is less that 40% of radius.
Permafrost: [4 levels, requires Heavy pushes 2 or Heart freeze 1]
Increases stun chance by 15% per node level. Increases stun duration and freeze duration by 6% per node level.
Unstoppable blows: [3 levels, requires Heavy pushes 2]
When attack is started gain 2 second buff which increases mage’s stun avoidance by 50 per node level and decreases stun duration on him by 10% per node level.
Disturbed calm: [1 level, requires Unstoppable blows 2]
Sometimes gain a buff for 5 seconds which is able to stack up to 5 times and increases attack speed with Shatter Strike by 10% per stack. Buff appears with 20% chance on enemy killed, 40% chance on taking damage and 100% chance when mage is stunned. Each stack has individual duration so it’s quite hard to keep all 5 stacks. Also there’s 0.5 second internal cooldown on gaining buff from kills and damage so it’s impossible to get several stacks after killing a bunch of enemies or taking a series of hits. Though stun condition isn’t limited like that. It is even possible to get 2 stacks after taking damage and being stunned by that damage.
Easy way: [5 levels]
Reduces skill’s mana cost by 2 per node level. But there’s 7% chance per node level to lose 1 mana per each enemy being hit with this skill.
Echo waves: [4 levels, requires Easy way 1]
Waves have 15% chance per node level to continue their movement making full new circle with 15% increased speed. These waves deals 20% reduced damage, can’t freeze, push, knock back and can’t cause wave clash. Their chance to apply other on hit effects is decreased by 50%. Also they are unaffected by “Easy way” mana loss. So it’s pure damage source. Visually these waves are “weaker” and their snow trail has much lower density. These waves move slightly above main waves for to stay being visible (same cause of movement speed difference). Important to note that these waves have the same damage interval mechanics though they do not share it with main waves. Also echo waves are independent of further mage’s attacks. They orbit mage even during his movement. Their position / direction is also independent of mage’s angle of rotation.
Long echo: [1 level, Echo waves 2]
Echo waves have 60% chance to make another circle. Their damage additionally decreases by 20% and their speed additionally increases by 15%. This second echo appears ONLY if first echo appeared. This means that real chance to see double echo after initial strike is 0.15 * 4 * 0.6 = 36%.
Storm front: [5, requires Echo waves 2]
Adds 1 lightning damage, 20 lightning penetration and 20 cold penetration per node level. Wave clash also gets this bonus and it is doubled with “Martial Art” node. Any enemy caught by wave clash gets this lightning damage twice. Also must note that “Martial art” node doubles penetration bonuses ALSO.
Martial art: [1 level, requires Storm front 2]
Shatter Strike has its speed penalty reduced by 60% and performing as a 4-strike combo. Each next strike recovers 20% of penalty and increases area of effect by 20% (~ 10% radius). Wave clash appears after 4-th strike only and the combo is reset. So player sacrifices regular wave clashes to get greater attack speed / wave frequency and increased AoE (60% max). Duration of combo-effect is 2 seconds. If player performed 2 attacks but delayed 3-d attack for 2 seconds or more, next attack will be made as 1-st - not 3-d.
Guided storm: [6 levels, requires Martial Art 1]
Waves appear behind the mage as an angle of 20 degrees per node level. Area of effect is increased by 5% per node level. Echo waves still cover full area circle. With this node mage can’t damage enemies behind him. On the other hand, waves appear closer to a front and reach targets sooner. In fact attacks become even faster: -120 degrees means that 1/3 of the way is already passed.
Warmthbane: [2 levels]
15% chance per node level to apply chill effect on damaged enemy. If it’s affected by Ignite there’s equal chance to convert one stack of Ignite to Frostbite. Duration of Ignite and Frostbite are independent. Created Frostbite stack always has maximum duration.
Biting frost: [10 levels, requires Warmthbane 1]
10% chance to apply Frostbite effect on enemies caught by wave clash. “Martial Art” node doubles this chance.
Grand Shatterer: [1 level, requires Biting frost 2]
Slayed enemies has 40% chance to become a frozen statue that explodes 0.5-2 seconds later, leaving no corpse and dealing damage enemies around. Yes, explosion delay is random. Also explosion damage is not a part of melee attack and can be increased via “Jaws of Winter” node, cold damage bonuses or attributes (+6% per INT / DEX). Explosions are also this skill’s damage so they can cause further “Grand Shatterer” activation (chain of explosions). Though explosion radius is small. Also there is a 1 sec time interval after damaging enemy with Shatter Strike when ANY damage allows this node to activate - very important for dealing damage with DoT effects.
Frag wave: [5 levels, requires Grand Shatterer 1]
Explosion area increases by 30% per node level. Chance to deal critical damage with explosions increases by 20% per node level. It is very useful with “Frost maims”, “Bury the weak” and other nodes with critical effect.
Shell of shatters: [1 level]
For every exploded frozen statue mage gains stacking buff that increases armor and cold protection by 50 per stack. Any enemy attack has 20% chance to remove one stack and cause Grand Shatterer’s explosion. Stack duration is 15 seconds. It is individual for every stack. Maximum amount of stacks - 10.
Path of Ruin: [2 levels. requires Shell of shatters 1]
Gain 1 mana per node level after each explosion. “Shell of shatters” lasts 5 seconds longer per node level. Mana recover works after “Shell of Shatter” explosions also.
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