UBV4 Challenge

Description
Defeat ITRTGv4 with increased difficulty.

Unlock Condition
Defeat ITRTGv4 normally.

Restrictions
The stat nerf that the UBv4s normally receive is reduced by (1 + challenges completed) * 20%. This means that for the final challenge, you will be facing them with their full stats.

Reward
Challenge Points: 20 Statistics Multi: 1,500,000

Each completion will reduce the timer for UBv4 fights by 1 minute.

Completions to Max
5

Recommended Stats
Unknown.

Strategy
The first UBV4 Challenge is comparable in difficulty/length to the time it takes to defeat the UBV4s normally. You might need to wait a little longer, for an extra ITRTG fight or two, if you're relying on the stat nerfing.

Later UBV4 Challenges -- and in particular the final challenge -- are not recommended unless you can defeat the UBV4s without the stat nerfing. Without that, the only real power growth you can obtain for fighting the UBV4s comes from the "Physical HP+" and "Mystic Regen+" Mights, and the "Dimension Beamer" SpaceDim.

The advice in A complete guide to V4s applies here. You'll want high level pets with fully upgraded & gemmed Tier 3 (or even Tier 4) equipment. You'll also want high numbers of Shadow and Light Clones.

Use your Shadow Clones to boost the two relevant Mights, and fight the UBV4s when you're strong enough. There's really no other strategic option.