ArroganteRitualHelper

Both bars read their buff from Blizzard's Cooldown Manager. Open the Cooldown Manager settings and put Diabolic Ritual and Dominion of Argus into the tracked buffs (the icons, not the bars). A bar only shows while its buff is up, or while the bars are unlocked.

How the bars work
Each bar is a timeline: the left edge is now, the right edge is a few seconds ahead ("Seconds shown"). The small numbers above mark the seconds.
- White line: where a Hand of Gul'dan started right now would finish. While you're casting, it's where your current cast finishes. It's hidden during the global cooldown, because you can't start a cast yet.
- Green zone: from now until the white line.
- Faint marker: Hand of Gul'dan's cast time with your current haste. That's where the white line comes back once the global cooldown is over.

Diabolic Ritual bar (purple)
Goal: Hand of Gul'dan should finish just after Diabolic Ritual runs out, so it uses the Demonic Art you get from it.
- The purple bar is the time the Ritual has left. Every Soul Shard you spend makes it 1 second shorter.
- Good: the purple bar ends left of the white line. Then the cast finishes after the Ritual.
- Too early: the purple bar still reaches past the white line.

Dominion of Argus bar (orange)
Goal: at 2 stacks, see whether one more Hand of Gul'dan finishes before Dominion of Argus runs out.
- The orange bar is the time Dominion has left. The bar only covers Dominion's last few seconds (default 4).
- The number left of the icon is Dominion's stack count. It shows from 2 stacks on.
- Good: the white line is inside the orange bar. Then the cast finishes in time.
- Too late: the orange bar ends left of the white line.
- In combat the game hides buff timers and stacks from addons. So the bar can't wait for the last seconds or for 2 stacks: it stays up for the whole buff, and the orange bar fills it until Dominion's end comes into view.

Moving the bars
Tick "Unlock bars to move them" (or type /arh move). Each bar gets a blue handle: drag it to move the bar, right-click to lock both again. While unlocked, both bars show a made-up example. You can also type exact positions, in pixels from the middle of the screen.

Always on
- Cast time: "time left / total" seconds next to your cast bar.
- Cooldown Manager buff icons show their timer with one decimal, above the icon. Buff bars show one decimal too.
- The end caps (the gryphons) on the main action bar are hidden.

Slash commands
/arh or /ritualhelper - open the settings
/arh move - unlock or lock both bars
/arh pos X Y - place the Diabolic Ritual bar
/arh dompos X Y - place the Dominion of Argus bar
/arh reset - put both bars back in their default spots