Already finished all the challenges from the new event Honestly Idk why I'm still waiting for the mod
Here are some tips:
Recommendation: Start from DP-D to DP-A.
Most Annoying Enemies:
DP-D: Frostnova, two phases, will summon crystal tower during the 2nd phase, use everything you got (Except your most powerful operators-save them, all 12 of them, for the Final Battle) on her. I recommend withdrawing your Vanguards back to the last stand, far away from her and use minimum operator to force her into the 2nd phase, as it's almost impossible to avoid the Crystal tower and Fr-Phase2 frostburst AOE.
DP-C: Bulldozer& Cicerone Archer (Also that hammer guy) , the previous one took up 3 blocks, the later two are threats to the comm center. As you only have 1 hp seal, you cannot lose any comm center. Recommendation: 2 Heals& 3 Defenders, 1-2 Caster to take out Bulldozer.
DP-B & DP-A: Absolute minimum effort n Challenge, I use basically no Elite/elite 1 operator combo to pass, save your operators for the latter bases.
Final Stage:
Annoying: Elite Bulldozer, Elite Sarkaz Swordsman(Absorb hp+AOE), Elite Sarkaz Archer, aeroplanes that sneak pass.
Not so Annoying: Basically anyone else.
OH GOD WHY DO YOU EXIST: Hymnoi Hero and Warrior, for each base you capture, each of two (That is, a total of 4) will appear.
Both of them will draw your Operator's Prioritize attack, so choose to engage them wisely.
Hymnoi Hero: Annoying af, rather fast mover, requires 3 Block. periodically throw a bottle of sand that does minimal AOE damage, which lowers the affected Op's Block by 1 (3-2, 2-1) for around 10 sec, will not attack otherwise. Upon defeated, leaves a bottle that constantly heals your Operators by 3x3, with 1 extra block each side middle.
Hymnoi Warrior: Not so Annoying, but still a hot potata. One block is enough to stop him but he do attack when being blocked and do rather big damage so watch out. Slow movement, appear with invincibility lasts for 1-2 minute(still can be attacked and will trigger effect). Upon being attacked, constantly spawn arrow rains that deal real damage to all operators(that means no Art/Phy defense) as long as still under attack. Upon defeated, daze Close enemies (1x1 square all around him, as well as the one he stands on).
Even if you've saved your best Op's for this occasion, they are still a pain in the bum, prey for mods if you don't have, let's say, around 30 E2 operators..