Platinum: When you buy or sell in the Market — Platinum is the currency used on both ends
The market allows players to buy and sell specific items using Platinum currency
Legendary Crest: Use when opening an Elder Rift to add 2 modifiers to the Rift. Completing the Elder Rift grants Fading Embers to all party members, and guarantees you a Legendary Gem and 3 Runes. (300 Eternal Orbs)
платина, пока неизвестно что с ней делать.
https://diablo.blizzplanet.com/blog/comments/diablo-immortal-technical-alpha-systems-preview
Platinum: When you buy or sell in the Market — Platinum is the currency used on both ends
The market allows players to buy and sell specific items using Platinum currency
Legendary Crest: Use when opening an Elder Rift to add 2 modifiers to the Rift. Completing the Elder Rift grants Fading Embers to all party members, and guarantees you a Legendary Gem and 3 Runes. (300 Eternal Orbs)
Legendary Crest (3000 Platinum) — Daily Stock 100/100. Daily Purchase Limit: 1/1.
Т.е. по сути всё что угодно.