The Undermine(d) tier set effect is partially shared between all tanks, and follows a simple pattern. The 2-piece has a low (1.5ppm) chance to apply a major defensive effect - for us,
Icebound Fortitude - for 4 seconds and a 15% damage buff (
Luck of the Draw!) for 10 seconds. These effects trigger simultaneously and both are reactive procs triggering from any damage taken according to the tooltip. For some reason, the spells are flagged to also trigger when receiving direct healing, but we will assume this is unintended in this article, at least until we get to playtest this on PTR.
As usual, the effect itself is a whitelist of common spells. It also does not include pets or guardians, which means that until this is changed or fixed, it will also not apply to
Dancing Rune Weapon-copied damage or your ghoul.
The 4-piece effect combos off the 2-piece 10 second buff to add two additional effects, along with increasing its duration to 12 seconds:
Again, this is not testable on PTR, but spell data gives us two important clues in its implementation: the addition of a
Chain Targets flag to the damage effect of
Death Strike and
Death Knight Blood 11.1 Class Set 4pc increasing this to 3 (instead of a server-side script to cast
Death Strike multiple times), along with it being the only part of
Death Strike to have received this flag, strongly hints at this. As
Dancing Rune Weapon casts the same spell, it is possible that
Dancing Rune Weapon will echo this cleave, but this is something that will require PTR access to test.
How Strong Is It?
Honestly, it is
very weak, particularly considering our current tier set.
Offensively, thanks to a small bug that has gone unfixed during the entire season, it is possible to keep
Piledriver (our current 4-piece) at its maximal value without losing on resources while doing so. This effectively means that our current 4-piece is a net 6% damage at all times. The new 2-piece adds a random proc with 30% expected uptime once you have the 4-piece, summing up to ~4.5% bonus damage before factoring in the two other effects of the 4-piece.
Death Strike being able to cleave is mostly inconsequential in raid, particularly as it is on an uncontrollable proc. We'll get back to this detail later in the article; if you assume that you have three targets permanently near you, you can expect to gain a bonus 580% AP's worth of physical damage (before any Hero talent or Runeforge shenanigans come into play) per
Death Strike while
Luck of the Draw! is active. Since this proc is uncontrollable and can effectively trigger at any moment, there is no way to pool or bank for it.
The cost reduction on
Death Strike is even more unnoticeable and feels almost like an afterthought; taking an absolute upper bound of four
Death Strike per proc of
Luck of the Draw!, you may look forward to one extra
Death Strike every 3 minutes.
Defensively, this tier set's only value is the meager indirect value from bonus damage through Leech (and
Voracious if you play it), and a bonus 6 seconds of
uncontrollable Icebound Fortitude per minute that procs after you take damage - assuming it being able to proc off healing taken is a bug. That's it. Unless you count the extra
Death Strike, that is all you get defensively. Even our current tier set's 2% constant damage reduction was more impactful than this.
Potential Bugs
The only noticeable bug in implementation is in how
Luck of the Draw! can be triggered. Despite the tooltip mentioning that it procs off damage taken, spell data indicates that it can proc off both damage and healing taken. This is very likely unintended, but fixing it has severe ramifications.
Most raid fights and even a large amount of Mythic+ dungeons have periods of time when no damage is taken. Raid encounters prominently display this, and if our tier set can only be triggered by taking damage, there will be a somewhat perverse incentive to fish for more procs during downtime by stepping into non-lethal sources of avoidable damage. This has been a prominent "feature" of previous tier sets, and indicates that the learning that being incentivized to take damage to gain bonus throughput is
not fun. Worse still, the chance for the four seconds of
Icebound Fortitude to be completely wasted if it applies after the damage is taken is notoriously high.
Changing this tier set's activation to damage
done would fix all of this, and incentivize actually pressing your buttons - to an extent. The tier set's proc chance is still RPPM, and so, doing so would only add more chances rather than increasing the uptime significantly.
Reactive Defensive Cooldowns and You
The fundamental design of the tier set also deserves a mention, as the tuning point of it is not the only issue. The most memorable tier sets in recent history have all had one of two possible aspects:
- They provided a constant, noticeable gain in power that was both reliable and controllable (Gravewarden Armaments, The First Eidolon's Soulsteel for us)
- They provided a controllable, noticeable gain that was tied to the player's performance and actions and could be consistently relied on (no Blood Death Knight tier set since our spec rework in Legion has achieved this; other specs, such as Protection Paladins, have had tier sets that directly amplified a cooldown based on performance outside of it: Entombed Seraph's Radiance)
This tier set manages to not only achieve neither - by being too poorly tuned for the first and completely uncontrollable for the second - but it manages to do so while being frightfully convoluted: 4 seconds of
Icebound Fortitude at random times triggerable from
anything (right now), a short burst of bonus damage after managing to trigger the set (which is completely out of your control), a pitiful amount of cost reduction on
Death Strike and a random damage-only cleave effect on
Death Strike that may or may not line up while additional targets are up, depending on whether you managed to proc it at the right time.
Tying all of these effects to an active cast - say,
Consumption/
Blooddrinker (effective 2ppm instead of the 1.5ppm of the tier set) - would already be a breath of fresh air in terms of control. Simply changing the activator of
Luck of the Draw! from a random reactive proc to
Consumption/
Blooddrinker while leaving all other elements of the tier set untouched would allow the player to get back in control, turning this set from an uncontrollable weak set to a moment of defensive and offensive strength centered on a core spell that is firmly in the hands of the player, triggerable at will and available as and when they need it.
