Evoker: Sky-Walk In Mid-Air (Gamebreaking) (Patreon)

This is one of the most gamebreaking uses of lag I can remember.

Veteran patreons will know that if you trigger lag, eg using Lag7,

https://mega.nz/#!u5QWmDJL!ifiZLTd3uQDK0lQXGafRUw7Enrl-DQ6OCWxpTEetXIw

or simply pulling the cable out of your modem for a few seconds. that you can extend the effect of any speed buff for 8 seconds before you disconnect. This can be used for all kinds of things from capture the flag battlegrounds to speed-running dungeons.

One I had somehow overlooked is the Evoker ability, Deep Breath

https://www.wowhead.com/spell=357210/deep-breath

This actually propels your dragon into the air and moves them forward a short distance without loss of height. When extended with lag and paired with the Heroic Scale Commander talent "manoeuvurability" the fire animation stops but you can simply walk about in mid-air for 8 seconds + the 2 initial seconds of the ability.

This allows you to get out of bounds, stay out of enemy range, and simply move faster in pvp an pve scenarios. It can trivialize carry-the-flag pvp battlegrounds and skip through dungeons. Because it is usable in literally any type of content it can be quite gamebreaking.