Hi! I will try my best to explain to you the types of cosmetics in the game.
MechaStorm I is a subevent (like Enforcer Event, Viper Event, Resistance Event,… or the recent Mythic Pantheon (Greek Gods) Event), which means their cosmetics (skins/sprays/portraits,…) are available all year round and will NEVER disappear. (MechaStorm I skins are: Mecha Tyrael, Mecha Rehgar and Xenotech Abathur.). Subevent cosmetics’ prices WILL be reduced after a while (about 2 weeks or sometimes, until the Seasonal Event (that it was released alongside with) ends).
On the other hand, MechaStorm II is a Seasonal Event, a Summer Event to be precise. Seasonal Events are divided into 4 seasons and the Event’s theme doesn’t necessarily match the season’s theme. All Seasonal Events so far:
- Spring:
Lunar Festival Events were Spring Events of 2015, 2016, 2017 and 2018.
Caldeum Complex was the Spring Event of 2019.
Fragments of the Dark Nexus is the Spring Event of 2020. (This is the current Seasonal Event.).
- Summer:
Sun’s out, Guns out was the Summer Event of 2017.
Nexomania was the Summer Event of 2018.
MechaStorm II was the Summer Event of 2019.
- Fall/Autumn:
Hallow’s End Events were Fall Events of 2015, 2016 and 2017.
Fall of King’s Crest was the Fall Event of 2018.
Scarlet Heist was the Fall Event of 2019.
- Winter:
Winter Veil Events were Winter Events of 2015, 2016 and 2017.
Toys I was the Winter Event of 2018.
Toys II was the Winter Event of 2019.
Now that you know all the Seasonal Events, here’s how their cosmetics “work”. Seasonal Events’ cosmetics are available for a limited time and will return annually. For example, the current Spring Event is Fragments of the Dark Nexus, so in the shop, you can find its cosmetics AND all previous Spring Events’ cosmetics (like Caldeum Complex’s and Lunar Festival’s ones). The prices of Seasonal cosmetics WILL be reduced when they return in the following years, NOT after 2 weeks of their initial release (so you have to wait at least 1 year to get them with reduced prices).
Finally, there are limited-time cosmetics like mounts that cost golds instead of shards/gems (Ex: Wonder William) and limited-time skins (Ex: Deathranger Nova) that, of course, are only available for a limited time. Some MAY return in the future after their initial release, but no one knows for sure which ones will return, when they will return and maybe some won’t return at all.
I can see that you’re interested in the Mecha Yrel skin (I have it, it has beautiful animations and effects.) from MechaStorm II Event (that also has Mecha Valla and Xenotech Malthael). Like I said, MechaStorm II was a Summer Event, so its cosmetics (including Mecha Yrel skin) WILL return with this year’s Summer Event (which is the next Event, btw) and their prices are also reduced! So you will have to wait just a bit longer to get Mecha Yrel with a discounted price. (If you want to know more about the discounted prices, just ask me.) =))
Maybe, no one knows for sure if there would be MechaStorm III or not.