When you reach a certain VIP level, the following will be added to the Mission screen under the "Daily" tab:
Level 5...Consume 880 Gem
Level 8...Bonus: Vault Key
Level 10...Bonus: Tempering Spark
Level 13...Bonus: [All] Fighter's Shards
The benefits upon reaching certain VIP levels can be checked at the upper portion of the Home Page, with the label VIP level.