You are treated as killing all players who die directly due to an explosion caused by Detonation.
Interestingly, a player with Living Bomb or Volatile Zombie is ALSO treated as killing all players who die directly due to their effect being detonated; this is not the case when a player's items or Defective Turret are detonated; a detonated BOOM-erang effect won't have the player who gave it be counted as killing (unless they're the detonator.) (If you detonate your own effect and kill a player, you won't be treated as killing them twice.)
Set/released explosives are essentially stored in their connected remotes, so they only detonate during the detonation of their remotes. (Note that they do explode on the space stored in the remote rather than on the space of the player with the remote.) Also, remotes are "detonated" even if a connected explosive does not exist; the remotes are simply removed from the game in this case. This applies to ACME TNT Detonator, Frost Mine Activator, Glue Mine Activator, Sheep Activator, and Spider Mine Remote.
Doom a player, causing that player to inevitably die after 25 turns. This death removes all death preventing effects from the affected player, bypasses Death Immunity and spawns an evil Doom Guard for the caster for a short duration.
Cast a spell of mathematical evil, sending all players who currently stand on a prime number back a number of spaces equal to the number of that prime number in the list of all prime numbers, up to 25 spaces. For example, players on space 2 get sent back 1 space, whereas a player on space 29 (the 10th prime) gets sent back 10 spaces.
All players on the first 25 prime numbered spaces move back an amount of spaces equal to their space number's placement in the list of prime numbers, with 2 having the 1st placement and 97 having the 25th placement; players on prime numbered spaces over 97 move back 25 spaces.
Cast this spell on a player to cause 4 magic runes to appear randomly around them. You can later activate these runes with your newly acquired Activate Runes Of Guidance skill, sending anyone who stands on top of a rune 12-19 spaces forwards. The skill disappears after 2 rounds if not used.
Target any player: You gain an Activate Runes Of Guidance skill for 2 turns that is connected to runes that are created on 4 random spaces within a 15-space radius of the target.
Cast a spell of justice! The player who is leading moves back 15 spaces. The player who is at the back moves forward 15 spaces.
The player on the highest space moves 15 spaces back, while the player on the lowest space moves 15 spaces back.
If every player in the game is on the same space, this spell does nothing.
If 2 or more players are tied for first, only 1 player randomly selected from them will move 15 spaces back. If 2 or more players are tied for last, only 1 player randomly selected from them will move 15 spaces forward.
Blind, Burden, Curse Of Cold, Curse Of Relativity, Curse Of Resurrection, Curse Of Riches, Cursed Wounds, Death, Deny, Disarm, Doom, Evil Barrier, Inverted Dice, Life Link, Liquidize, Living Bomb, Mark For Death, Polymorph, Scare, Shatter, Slow, Spellsteal, Steal Item
Blessing Of Vengeance, Cards Of Fate, Defensive Barrier, Empowered Dice, Energize, Focus, Guardian, Life Shield, Momentum, On Love's Wings, Remove Curse, Revive, Runes Of Guidance, Save Point, Soul Speed, Speed Boost, Spell Reflect, Spell Shield
Spell reflectors and redirectors work vs. a player-cast spell by completely blocking a cast spell's effect and then making the player with the reflector/redirector cast a new spell (or up to 2 new spells for Ley Prism) with the same name (and effect) as the blocked spell.
Spells cast with reflectors and redirectors bypass Silenced.
Reflecting or redirecting Life Link can still end up with both you and the original caster linked under the Debuff.
If activating vs. a player-cast Spell, a Spell cast with reflectors and redirectors can trigger any relevant spell-triggered effects and can apply piercing effects.
If activating vs. a non-player-cast Spell, see below under In-Event Non-Player Spellcasting.
In the following events, players can "cast" specific spells. (Doing this bypasses Silenced, does not count for Magical Mind, and will not trigger any spell-triggered effects.) Most (but not all) of these events allow doing this with any Spell item/skill charged with an applicable spell.
While Spells cast in the listed events are quite similar to Spells cast by players, they are distinct from them; when they are reflected or redirected, the newly "cast" Spell can trigger spell immunity or spell protection but will not activate any other spell-triggered effects. However, if such a Spell is redirected to another player who then reflects or redirects it, the newly cast Spell can trigger ANY relevant spell-triggered effects.
The Cursed Gate in the Archaeology Dig is somewhat like the events listed above; it can trigger spell immunity and some (but not all) forms of spell protection, and it won't activate any spell-triggered effects when reflected. However, it cannot trigger other spell-triggered effects like Magic Affinity and Amethyst Necklace.
If Silenced blocks a Spell, no spell-triggered effects activate.
If a piercing effect accompanies your Spell, no form of spell protection triggers, though other spell-triggered effects may still trigger (including a form of spell immunity.)
If any form of spell immunity or spell protection triggers for a targeting spell, no effects later in the order trigger, though any effects before it in the order may still trigger. If any form of spell immunity triggers for a non-targeting spell, the player it triggered for is not considered to be "affected" for an effect like Rylai's Crystal Scepter.
If you would target yourself with a Spell which you normally cannot target yourself with (e.g. On Love's Wings with V-Card), Cast-Triggered and Target-Triggered effects do not activate.
For interactions with spells in events, see above under In-Event Player Spellcasting and In-Event Non-Player Spellcasting.