How to Play Idoneth Deepkin in Warhammer Age of Sigmar (4th Edition)

The Idoneth army identity rests on two things: ambushing from reserve, and the tides.

• Ethersea ambush (Ethersea Voyagers / Raiders from the Deep). You can hold a regiment back in reserve and then bring it onto the battlefield later, arriving near a battlefield edge and away from enemy units. This is the core of the faction's hit-and-run feel: you deploy fewer models on turn one, then wash a wave of units onto a flank exactly where you want them. Check the current wording for the exact distances and timing, as these are the kind of numbers GW tunes over time.
• The tides. Once per battle round you activate a tidal ability, and the army rewards you for progressing down a track. There are two tracks. Tides of the Sea is the defensive/mobility track (effects reported as: harder to hit if you didn't charge, then run-and-still-shoot-or-charge, then a strike-first effect). Tides of the Storm is the aggressive/repositioning track (effects reported as: reposition a unit toward a battlefield edge, then reduce enemy Rend against you, then a critical-hit mortal-wound effect on your melee). You can switch tracks, but switching resets your progress, so plan several rounds ahead.
• Akhelian/Namarti synergy. The army is designed so its aristocratic Akhelian cavalry and its enslaved-soul Namarti infantry support each other. Treat them as a combined-arms force rather than spamming one keyword.

Because the precise numbers and the strike-first turn matter enormously, edition-stamp your knowledge: this is 4th edition behaviour, and you should confirm the exact tidal names, order and effects on your own battle traits sheet.

The core battletome gives Idoneth four battle formations. Pick one at list-building; it shapes how the whole army plays.

• Namarti Corps - your Namarti infantry re-roll run and charge rolls while near an Akhelian unit. Best if you want reliable, aggressive Namarti pushes.
• Akhelian Beastmasters - your Akhelian mounts' companion (mount) weapons hit better. Best for eel- and shark-heavy cavalry lists that live off mount damage.
• Isharann Council - boosts your Isharann casters/rituals when they operate together. A magic-forward pick, generally seen as more niche.
• Soul-raid Ambushers - leans into the Storm-tide repositioning, letting you reposition more than one unit at a time. Best for a mobility/teleport-heavy playstyle.

There is no single 'correct' answer, but community coverage generally rates the mobility- and cavalry-focused options (Beastmasters, Soul-raid Ambushers, Namarti Corps) ahead of the pure-magic Council. Confirm each formation's exact wording in your faction pack, and remember the Scourge of Ghyran book adds further options not covered here.

• Akhelian Morrsarr Guard (eel cavalry) - your hammer. Fast, hit hard on the charge, often carrying a burst of mortal-wound output. A staple.
• Akhelian Ishlaen Guard (eel cavalry) - the anvil version of the eels: tougher and better at pinning enemies in place while surviving.
• Akhelian Allopex (shark) - a high-damage, mobile threat that hunts key targets; strong at chewing through units or picking off support pieces.
• Namarti Thralls - your close-combat infantry block; cheap bodies that do real work when buffed and supported by Akhelians.
• Namarti Reavers - skirmishing ranged infantry for chip damage and objective play.
• Isharann casters (e.g. Tidecaster/Soulscryer types) - your magic and utility: buffs, the ambush/reserves support, and control tools. The Soulscryer in particular helps orchestrate where your reserves arrive.
• Akhelian King / Volturnos - hard-hitting cavalry heroes to lead the eel line and add combat punch plus leadership.
• Eidolon of Mathlann (Aspect of the Sea / Aspect of the Storm) - a big centrepiece hero: the Storm aspect as a beatstick, the Sea aspect as a caster/support piece.
• Akhelian Leviadon - the army's monster: a durable, dangerous platform that anchors a line.

Exact roles, warscroll abilities and points shift with updates, so treat the above as role guidance rather than a fixed tier list.

Idoneth is a finesse army. Your win condition is manoeuvre: use ambush and repositioning to pick favourable fights, land buffed cavalry into a soft target, and control objectives while denying the opponent the clean counter-charge.

A typical plan:

1. Deploy light. Hold a regiment in reserve so you keep options open and reduce what the enemy can hit turn one. 2. Plan your tide track. Decide early whether you want the defensive Sea track or the aggressive Storm track for the opening rounds, since switching resets progress. Many players aim to line up a big strike-first or crit-mortal turn with a decisive charge. 3. Choose the moment to wash in. Bring reserves on near an edge to threaten a flank or objective, ideally where the enemy can't punish you immediately. 4. Buff, then commit. Stack your formation and hero buffs onto the unit that's about to charge rather than trading piecemeal. Idoneth reward concentrated, well-timed hits. 5. Score and reposition. Use your speed to hold objectives and slide off contested ones, letting mobility do work your raw damage can't.

The throughline: don't brawl fairly. Set up the fight you want, then hit it with everything at once.

• Trading fragile units piecemeal. Idoneth models are not especially durable for their cost. Feeding cavalry in one unit at a time, unbuffed, wastes them. Commit together, buffed.
• Fighting the tide instead of using it. Switching tidal tracks resets your progress. Flip-flopping means you never reach the powerful later abilities. Pick a plan and follow the track.
• Mistiming the ambush. Bringing reserves on too early gives up the surprise; too late and the game is decided. The arrival turn is a real decision, not an autopilot.
• Spamming one keyword. The army is designed around Akhelian and Namarti synergy plus Isharann support. All-eel or all-shark lists give up buffs and board presence and can be out-resourced.
• Where they struggle: against opponents who are faster than expected, who screen well against ambush drops, who bring heavy anti-magic, or who simply out-muscle you in an even fight. If you can't dictate the terms of engagement, the fragility shows. High-model-count horde and gunline opponents that punish your soft bodies are classic bad matchups.