Q1: If the Security effect, the "when security is checked" effect, and the "when security is reduced" effect are triggered simultaneously, in which order do they activate?
Security] effects are activated first. Security] effects, if checked, will be activated immediately without pending activation. Other triggered effects are activated from the turn player's side.
Lv.6 Imperialdramon: Fighter Mode BT20-020 SR Mega | Virus | Ancient Dragonkin [Digivolve] [Imperialdramon: Dragon Mode]: Cost 2 <Raid> <Piercing> (When this Digimon attacks and deletes an opponent's Digimon, it performs any security checks it normally would.) [When Digivolving] Your opponent can't play Digimon or Tamers by effects until the end of their turn. Then, if [Imperialdramon: Dragon Mode] is in this Digimon's digivolution cards, trash your opponent's top security card. [All Turns] [Once Per Turn] When your opponent's security stack is removed from, delete 1 of their Digimon with as much or less DP as this Digimon.
Lv.6 Imperialdramon: Fighter Mode BT20-020 SR Mega | Virus | Ancient Dragonkin [Digivolve] [Imperialdramon: Dragon Mode]: Cost 2 <Raid> <Piercing> (When this Digimon attacks and deletes an opponent's Digimon, it performs any security checks it normally would.) [When Digivolving] Your opponent can't play Digimon or Tamers by effects until the end of their turn. Then, if [Imperialdramon: Dragon Mode] is in this Digimon's digivolution cards, trash your opponent's top security card. [All Turns] [Once Per Turn] When your opponent's security stack is removed from, delete 1 of their Digimon with as much or less DP as this Digimon.
Lv.6 Imperialdramon: Fighter Mode BT20-020 SR Mega | Virus | Ancient Dragonkin [Digivolve] [Imperialdramon: Dragon Mode]: Cost 2 <Raid> <Piercing> (When this Digimon attacks and deletes an opponent's Digimon, it performs any security checks it normally would.) [When Digivolving] Your opponent can't play Digimon or Tamers by effects until the end of their turn. Then, if [Imperialdramon: Dragon Mode] is in this Digimon's digivolution cards, trash your opponent's top security card. [All Turns] [Once Per Turn] When your opponent's security stack is removed from, delete 1 of their Digimon with as much or less DP as this Digimon.
Lv.6 インペリアルドラモン:ファイターモード BT20-020 SR 究極体 | ウィルス種 | 古代竜人型 「インペリアルドラモン:ドラゴンモード」:コスト2 ≪突進≫≪貫通≫ 【進化時】相手のターン終了まで、相手はデジモンとテイマーを効果で登場できない。その後、このデジモンの進化元に「インペリアルドラモン:ドラゴンモード」があるなら、相手のセキュリティを上から1枚破棄する。 【お互いのターン】[ターンに1回]相手のセキュリティが減ったとき、このデジモンのDP以下の相手のデジモン1体を消滅させる。