It was in a sigil, effects were (as I remember) inhabited by doomguard race, extra attack, extra speed, more nemesis creatures. My team was as below.
Edit: It happened again on a non-sigil battle.
========== CHARACTER ==========
Persephone, Shadow of Erebyss, Level 11142 Sorcery Mage
Achievement Points: 16357 / 35733 (46%)
Game Version: 0.10.4
Total Deity Points: 47021
Attack (Rank 100 / 100)
Your creatures have 100% (+1% per rank) more Attack.
Battlemage (Rank 50 / 50)
When your creatures attack, 50% (+1% per rank) of their Intelligence is added to their Attack to determine the damage dealt.
Defense (Rank 100 / 100)
Your creatures have 100% (+1% per rank) more Defense.
Echo (Rank 25 / 25)
Your creatures’ spells have a 25% (+1% per rank) chance to cast an additional time. This effect can repeat multiple times in a row.
Essence (Rank 162 / 300)
You gain 162% (+1% per rank) more essence from battles.
Health (Rank 100 / 100)
Your creatures have 100% (+1% per rank) more Maximum Health.
Intelligence (Rank 100 / 100)
Your creatures have 100% (+1% per rank) more Intelligence.
Mana (Rank 50 / 50)
Your creatures have 50 (+1 per rank) more Maximum Mana.
Meditation (Rank 1 / 1)
When your creatures defend, they recover 100% Mana.
Outspoken (Rank 1 / 1)
Your creatures are immune to Silence.
Speed (Rank 100 / 100)
Your creatures have 100% (+1% per rank) more Speed.
Spell Damage (Rank 100 / 100)
Your creatures deal 100% (+1% per rank) more damage with spells.
Spell Mastery (Chaos) (Rank 1 / 1)
Your creatures can equip Chaos Spell Gems, regardless of their class.
Spell Mastery (Death) (Rank 1 / 1)
Your creatures can equip Death Spell Gems, regardless of their class.
Spell Mastery (Life) (Rank 1 / 1)
Your creatures can equip Life Spell Gems, regardless of their class.
Spell Mastery (Nature) (Rank 1 / 1)
Your creatures can equip Nature Spell Gems, regardless of their class.
Spell Mastery (Sorcery) (Rank 1 / 1)
Your creatures can equip Sorcery Spell Gems, regardless of their class.
Spell Slots (Rank 5 / 5)
Your creatures can equip 5 (+1 per rank) additional Spell Gem.
Wild Magic (Rank 1 / 1)
At the start of battle, your creatures are given 3 random Spell Gems that belong to their class. These spells cost 0 Mana.
Ruh Rune: You gain 25% more Brimstone from battles.
Xil Rune: You gain 25% more Granite from battles.
Eda Rune: Your creatures’ Protect buffs also have a 25% chance to negate incoming damage.
Kih Rune: Enemies’ Frozen debuffs now only have a 15% chance to be removed at the end of each turn.
Omi Rune: Your creatures’ Ward buffs now also give them a 50% chance to avoid attacks.
========== CREATURES ==========
Level 25601 Brownie Loner +0 (Nether)
Brownie / Nature
Health: 435513
Mana: 74
Attack: 354863
Intelligence: 193564
Defense: 193564
Speed: 387125
Innate Trait: Independence
This creature’s attacks always deal critical damage. In addition, this creature has an independent 30% chance to dodge attacks.
Nether Trait: False Prophecy
This creature always has Curse. When this creature would take damage from Curse, the damage is dealt to the enemy instead.
Nether Trait: Mouth For War
After this creature casts a single-target spell on an enemy, it also attacks that enemy 2 times.
Nether Trait: Zero to One
This creature can’t cast spells directly. When this creature attacks, it casts one of its single-target spells. These spells cost 0 Mana.
Nether Aura: Nether Aura: Defense
This creature shares 25% of its Defense with its allies.
Artifact: Charge (Crafted)
Less Damage From Life: 60%
Additional Spell Gem Slots: 2
Afflict Frozen On Hit: 25%
Gain Shell On Hit: 23%
Afflict Frozen When Hit: 20%
Start Battle With Ward
Trait: Charge
Charge: At the start of battle, this creature attacks random enemies 3 times.
Gem of Breath of Life (Mana Cost: 24) | 62% Chance to Attack
Target recovers a massive amount of Health, even if it is dead.
Gem of Chaos Channeling (Mana Cost: 27) | Casts On Extra Target, 69% Chance to Attack, Duration Increased By 1
Target is afflicted with 3 random debuffs for 3 turns.
Gem of Chaos Orbs (Mana Cost: 16) | 62% Chance to Attack
Target’s spell gems are sealed for the rest of the battle.
Gem of Decay (Mana Cost: 19) | Generous, Casts On Extra Target, 65% Chance to Attack
Target’s artifact is decayed.
Gem of Homing Arrow (Mana Cost: 26) | Damage Increased By 27%, 59% Chance to Attack, Casts On Extra Target
Target takes a moderate amount of damage that ignores the target’s Defense. 100% of the damage is based on the caster’s Speed instead of Intelligence.
Gem of Icewolf Bite (Mana Cost: 31) | Damage Increased By 29%, Casts On Extra Target, 52% Chance to Attack
Target takes a large amount of damage and is afflicted with Frozen.
Gem of Mutilate (Mana Cost: 27) | Casts On Extra Target, 54% Chance to Attack
Target’s Health is set to 1. This spell cannot be cast manually, but has a 10% chance to cast when its owner attacks.
Gem of Purgatory (Mana Cost: 7)
Target is sent to the bottom of the Action Queue.
Gem of Rend (Mana Cost: 39) | Casts On Extra Target, 59% Chance to Cast Twice, 55% Chance to Attack
Target takes a moderate amount of damage and is afflicted with Bleed. This spell cannot be cast manually, but has a 30% chance to cast when its owner attacks.
Gem of Shellbust (Mana Cost: 21) | 61% Chance to Attack, Casts On Extra Target, Stat +/- Increased By 35%
Reduces target’s Defense by a moderate amount and deals damage equal to 200% of the amount reduced.
Gem of Steel Storm (Mana Cost: 32) | 28% of Potency Based On Health, 48% of Potency Based On Defense, Damage Increased By 39%
Enemies take a massive amount of damage. This spell cannot be cast manually, but has a 15% chance to cast when its owner attacks or is attacked.
Gem of Wormhole (Mana Cost: 18) | 55% Chance to Attack
Caster swaps positions with the target on the Action Queue. This spell cannot be cast manually, but has a 25% chance to cast when its owner attacks.
Level 21809 Apis Defender +2752
Apis / Life
Health: 588906
Mana: 72
Attack: 222476
Intelligence: 91608
Defense: 287910
Speed: 222476
Innate Trait: Vigilance
This creature intercepts attacks on its allies, but when it does, it takes extra damage equal to 10% of its Maximum Health.
Artifact: Nature Shield
Less Damage From Nature: 80%
Additional Spell Gem Slots: 3
Start Battle With Ward
Increased Dodge Chance: 14%
Immune to Stun
Afflict Scorn When Hit: 15%
Trait: Stank
Stank: Enemies deal 10% less damage and take 10% more damage for each debuff they have. This trait does not stack.
Gem of Affliction (Mana Cost: 29) | Duration Increased By 1, Generous, 63% Chance to Defend
Enemies are afflicted with a random debuff for 3 turns.
Gem of Ascension (Mana Cost: 10)
Caster gains a random trait. This spell cannot be cast manually, but has a 100% chance to cast when the caster defends or provokes.
Gem of Breath of Life (Mana Cost: 21) | Mana Cost Reduced By 28%, 58% Chance to Defend, 67% Chance to Refund Mana
Target recovers a massive amount of Health, even if it is dead.
Gem of Chaos Orbs (Mana Cost: 13) | Mana Cost Reduced By 21%, Class Swap: Nature, 53% Chance to Defend
Target’s spell gems are sealed for the rest of the battle.
Gem of Dispel (Mana Cost: 5) | Class Swap: Nature, Mana Cost Reduced By 38%, Casts On Extra Target
Target’s buffs and debuffs are removed.
Gem of Divinity (Mana Cost: 25) | 56% Chance to Refund Mana, 55% Chance to Defend, Mana Cost Reduced By 26%
All creatures are resurrected, recover 100% Health, and their buffs and debuffs are removed. The Action Queue is shuffled.
Gem of Guardian Force (Mana Cost: 18) | Class Swap: Nature, Mana Cost Reduced By 25%, 54% Chance to Refund Mana
Your creatures defend.
Gem of Fury Swipes (Mana Cost: 41) | Generous, Casts On Extra Target, 41% Chance to Cast Twice
Target attacks random enemy creatures 5 times. Each attack deals 25% normal damage.
Gem of Major Resurrection (Mana Cost: 30) | Class Swap: Nature, 54% Chance to Defend, Generous
Target is brought back to life with a large amount of Health.
Gem of Pestilence (Mana Cost: 32) | Generous, Duration Increased By 3, 62% Chance to Defend
Enemies spread 1 of their debuffs to all other enemies for 1 turn.
Gem of Shield Slam (Mana Cost: 18) | 72% Chance to Defend, Mana Cost Reduced By 21%
Target takes a moderate amount of damage and has a 35% chance to be sent to the bottom of the Action Queue. 100% of the damage is based on the caster’s Defense instead of Intelligence.
Level 50 Elf Barbarian +0
Elf / Nature
Health: 1121
Mana: 86
Attack: 346
Intelligence: 759
Defense: 190
Speed: 660
Innate Trait: Hate And Other Triumphs
The enemy creatures’ effects that activate when they die are ignored.
Artifact: Hate And Other Triumphs
Intelligence: 30%
Maximum Health: 30%
Additional Spell Gem Slots: 3
Afflict Frozen When Hit: 17%
Gain Shell When Hit: 18%
Immune to Snare
Increased Dodge Chance: 10%
Trait: Hate And Other Triumphs
Hate And Other Triumphs: The enemy creatures’ effects that activate when they die are ignored.
Gem of Ancient Prayer (Mana Cost: 33) | Duration Increased By 1, Generous, Casts On Extra Target
Your creatures gain copies of all the target’s buffs.
Gem of Breath of Life (Mana Cost: 18) | Class Swap: Nature, Mana Cost Reduced By 35%, 58% Chance to Attack
Target recovers a massive amount of Health, even if it is dead.
Gem of Chaos Orbs (Mana Cost: 15) | Mana Cost Reduced By 24%, 60% Chance to Refund Mana, 65% Chance to Defend
Target’s spell gems are sealed for the rest of the battle.
Gem of Defile (Mana Cost: 12) | Generous, 66% Chance to Defend, Mana Cost Reduced By 27%
Enemies are afflicted with Poison and Blight for 5 turns.
Gem of Dispel (Mana Cost: 6) | Class Swap: Nature, Mana Cost Reduced By 23%, Casts On Extra Target
Target’s buffs and debuffs are removed.
Gem of Divinity (Mana Cost: 47) | 71% Chance to Attack, 54% Chance to Refund Mana, Class Swap: Nature
All creatures are resurrected, recover 100% Health, and their buffs and debuffs are removed. The Action Queue is shuffled.
Gem of Firestorm (Mana Cost: 18) | Mana Cost Reduced By 15%, Generous, Class Swap: Nature
Enemies take a moderate amount of damage and are afflicted with Burn for 3 turns.
Gem of Homing Arrow (Mana Cost: 25) | Generous, Damage Increased By 33%, Casts On Extra Target
Target takes a moderate amount of damage that ignores the target’s Defense. 100% of the damage is based on the caster’s Speed instead of Intelligence.
Gem of Reincarnation (Mana Cost: 22) | Generous, Mana Cost Reduced By 24%, 58% Chance to Defend
Target is killed, then brought back to life with a massive amount of Health.
Gem of Splitting Arrow (Mana Cost: 35) | 40% Chance to Cast Twice, Damage Increased By 60%, 67% Chance to Defend
Enemies take a small amount of damage. 100% of the damage is based on the caster’s Speed instead of Intelligence.
Level 4050 Pilwiz Herbalist +400
Pilwiz / Nature
Health: 63218
Mana: 81
Attack: 51060
Intelligence: 29178
Defense: 26746
Speed: 38904
Innate Trait: Throat Slash
At the start of battle, afflict enemies with Bleed for 2 turns.
Artifact: Sorcery Shield
Less Damage From Sorcery: 80%
Additional Spell Gem Slots: 2
Afflict Frozen When Hit: 26%
Increased Dodge Chance: 21%
Start Battle With Ward
Gain Protect When Hit: 19%
Trait: Winter Has Come
Winter Has Come: At the start of battle, this creature afflicts 3 random enemies with Frozen.
Gem of Black Hole (Mana Cost: 18) | Generous, 68% Chance to Defend, Mana Cost Reduced By 27%
Enemies lose their additional, temporary traits gained during battle, and the caster gains a copy of them.
Gem of Black Ice (Mana Cost: 14) | Generous, Mana Cost Reduced By 37%, 69% Chance to Defend
Each enemy has a 50% chance to be afflicted with Frozen, and each of your creatures have a 50% chance to gain Invisible for 1 turn.
Gem of Breath of Life (Mana Cost: 17) | Class Swap: Nature, Mana Cost Reduced By 39%, 69% Chance to Defend
Target recovers a massive amount of Health, even if it is dead.
Gem of Chaos Orbs (Mana Cost: 13) | Class Swap: Nature, Mana Cost Reduced By 27%, 54% Chance to Refund Mana
Target’s spell gems are sealed for the rest of the battle.
Gem of Dust Cloak (Mana Cost: 10) | Generous, 62% Chance to Defend, Mana Cost Reduced By 39%
Your creatures gain Invisible for 1 turn but are sent to the bottom of the Action Queue.
Gem of Dispel (Mana Cost: 8) | Class Swap: Nature, Mana Cost Reduced By 23%, 44% Chance to Refund Mana
Target’s buffs and debuffs are removed.
Gem of Divinity (Mana Cost: 30) | Class Swap: Nature, 55% Chance to Defend, Mana Cost Reduced By 15%
All creatures are resurrected, recover 100% Health, and their buffs and debuffs are removed. The Action Queue is shuffled.
Gem of Permafrost (Mana Cost: 21) | 67% Chance to Defend, Mana Cost Reduced By 22%, 60% Chance to Refund Mana
Enemies that are Frozen are afflicted with Stun for 1 turn.
Gem of Whirlwind (Mana Cost: 33) | Generous, 59% Chance to Cast Twice, Mana Cost Reduced By 25%
Enemies take a moderate amount of damage that ignores 30% of their Defense.
Level 110 Darkscythe Pilwiz +6
Pilwiz / Nature
Health: 2093
Mana: 93
Attack: 1707
Intelligence: 810
Defense: 798
Speed: 1146
Innate Trait: Shadow Hook
Your creatures deal 10% more damage, and enemies deal 10% less damage, for each enemy that is afflicted with Bleed. This trait does not stack.
Artifact: Pandemonium Fever
Attack: 30%
Maximum Health: 30%
Defense: 15%
Maximum Mana: 11
More Damage To Life: 55%
Less Damage From Life: 55%
Increased Dodge Chance: 16%
Trait: Pandemonium Fever
Pandemonium Fever: At the start of battle, this creature casts Affliction.
Gem of Brain Freeze (Mana Cost: 15) | Generous, 52% Chance to Defend, Mana Cost Reduced By 37%
Enemies’ spell gems they’ve already cast in the current battle are sealed.
Gem of Breath of Life (Mana Cost: 30) | Class Swap: Nature, 54% Chance to Defend, 41% Chance to Refund Mana
Target recovers a massive amount of Health, even if it is dead.
Gem of Chaos Orbs (Mana Cost: 14) | Class Swap: Nature, 54% Chance to Defend, Mana Cost Reduced By 16%
Target’s spell gems are sealed for the rest of the battle.
Gem of Debilitate (Mana Cost: 10) | Class Swap: Nature, Casts On Extra Target, Mana Cost Reduced By 34%
Target loses access to all its non-innate and non-artifact traits for the rest of the battle.
Gem of Dispel (Mana Cost: 7) | Class Swap: Nature, Mana Cost Reduced By 16%, Casts On Extra Target
Target’s buffs and debuffs are removed.
Gem of Divinity (Mana Cost: 23) | Class Swap: Nature, Mana Cost Reduced By 33%, 56% Chance to Defend
All creatures are resurrected, recover 100% Health, and their buffs and debuffs are removed. The Action Queue is shuffled.
Gem of Equality (Mana Cost: 19) | Mana Cost Reduced By 32%, 52% Chance to Defend, 49% Chance to Refund Mana
Target’s stats are averaged.
Gem of Panic Attack (Mana Cost: 36) | 62% Chance to Refund Mana, Generous, 59% Chance to Defend
Each of your creatures attack a random enemy for 50% normal damage.
Level 14283 Siren Reaper +2804
Siren / Life
Health: 317136
Mana: 82
Attack: 111426
Intelligence: 188568
Defense: 51428
Speed: 145712
Innate Trait: Beautiful Sorrow
When one of your creatures dies, this creature gains their innate trait.
Artifact: Shake
More Damage To Death: 135%
Additional Spell Gem Slots: 2
Less Damage From Nature: 56%
Afflict Frozen When Hit: 17%
Immune to Sleep
Start Battle With Ward
Trait: Shake
Shake: When an enemy casts a spell, this creature has a 35% chance to interrupt it.
Gem of Breath of Life (Mana Cost: 20) | Mana Cost Reduced By 25%, Class Swap: Nature, 65% Chance to Defend
Target recovers a massive amount of Health, even if it is dead.
Gem of Call Death (Mana Cost: 24) | Class Swap: Nature, Mana Cost Reduced By 24%, Generous
Summons Death to periodically damage enemies until the end of the battle. Only one Death can be active at a time.
Gem of Dark Whispers (Mana Cost: 22) | Generous, Mana Cost Reduced By 20%, Duration Increased By 2
Your creatures gain Multicast for 1 turn.
Gem of Chaos Orbs (Mana Cost: 15) | 45% Chance to Refund Mana, Class Swap: Nature, Mana Cost Reduced By 17%
Target’s spell gems are sealed for the rest of the battle.
Gem of Divinity (Mana Cost: 25) | Class Swap: Nature, 67% Chance to Defend, Mana Cost Reduced By 30%
All creatures are resurrected, recover 100% Health, and their buffs and debuffs are removed. The Action Queue is shuffled.
Gem of Enlightenment (Mana Cost: 20) | Class Swap: Death, Casts On Extra Target, Generous
Target’s Attack is added to its Intelligence. Then, its Attack is set to 1.
Gem of Rain of Blood (Mana Cost: 17) | Generous, 50% Chance to Defend, Mana Cost Reduced By 23%
Enemies are afflicted with Bleed for 5 turns.
Gem of Requiem (Mana Cost: 28) | 46% Chance to Refund Mana, Mana Cost Reduced By 22%, Class Swap: Nature
Your creatures are brought back to life with a moderate amount of Health.
Gem of Splitting Arrow (Mana Cost: 34) | 43% Chance to Cast Twice, Damage Increased By 49%, 52% Chance to Defend
Enemies take a small amount of damage. 100% of the damage is based on the caster’s Speed instead of Intelligence.
Gem of Vacuum (Mana Cost: 13) | Generous, Class Swap: Nature, Casts On Extra Target
Caster gains the target’s trait.