Social Media Challenge: The Unkillable Wise Lurker

This is a Equal Opportunity ruleset game so All Monsters have the Opportunity ability.
Speed and HP is the trick here: higher speed will let you target enemy's low HP monster first, opening the way for your slower monsters to deal damage to higher HP enemy monsters. Keep lower HP monsters in front.

This is a Weak Magic ruleset game so Magic attacks hit Armor before reducing Health.
Protect, Repair, Rust are useful in this ruleset. Beware the opponent could choose only Melee and Ranged monsters, so keep a tank with Shield.

This is a Odd Ones Out ruleset game so Only Monsters with odd Mana costs may be used in battles.
There are no special tricks for this ruleset, but having an idea of mana points of a few monsters helps in predicting what your opponent can and cannot use.

Pos 1 Monster: Legionnaire Alvar

Abilities:
Void Armor - Magic attacks hit this Monster's armor before its Health
Giant Killer - Does double damage against targets that cost 10 or more mana
Demoralize - Reduces the Melee attack of all enemy Monsters
-1 to melee attack, it cannot be less than 1
Deathblow - This Monster does 2x damage if their target is the only Monster left on the enemy team

Pos 3 Monster: River Hellondale

Abilities:
Resurrect - When a friendly Monster dies it is brought back to life with 1 Health. This ability can only trigger once per battle
Inspire - Gives all friendly Monsters +1 Melee attack.
Dispel - When this monster hit an enemy, it clears all positive status effects on that enemy

Pos 5 Monster: Angelic Mandarin

Abilities:
Triage - Heals the friendly back-line Monster that has taken the most damage
Heal is max health divided by 3, rounded down. Minimum is 2.
Silence - Reduces the Magic Attack of all enemy Monsters